Message – June Quarter 2017 Estimating the NAIRU and the Unemployment Gap

Abstruse

Spare capacity in the labour market is an important input into forecasts of inflation and wage growth. This commodity describes how the Bank estimates one measure of spare capacity in the labour market – the gap between the unemployment rate and the non-accelerating inflation rate of unemployment (NAIRU). Model estimates of the NAIRU are highly uncertain and can change quite a bit as new data become bachelor. The estimates propose that the NAIRU has declined since the mid 1990s and is currently around five per cent.

What Is the NAIRU and Why Is It Important?

Labour underutilisation is an important consideration for monetary policy. Spare capacity in the labour market affects wage growth and thus inflation (Graph ane). Reducing it is also an finish in itself, given the Banking concern'south legislated mandate to pursue full employment. The NAIRU – or non-accelerating inflation rate of unemployment – is a benchmark for assessing the caste of spare capacity and inflationary pressures in the labour marketplace. When the observed unemployment rate is below the NAIRU, atmospheric condition in the labour market place are tight and in that location will be upward force per unit area on wage growth and inflation. When the observed unemployment rate is above the NAIRU, there is spare chapters in the labour market and down pressure on wage growth and aggrandizement. The divergence between the unemployment rate and the NAIRU – or the 'unemployment gap' – is therefore an important input into the forecasts for wage growth and aggrandizement.

Graph 1

Graph 1 Labour Market and Price Pressures

In exercise, the NAIRU – and therefore the unemployment gap – are non observed. This article sets out how the Bank currently estimates the NAIRU for the purpose of forecasting wage growth and inflation, and how estimates of the NAIRU have changed over fourth dimension.[ane]

The NAIRU can be divers in various ways and is sometimes used interchangeably with the broader concept of the unemployment rate associated with 'full employment'. In this commodity nosotros apply a narrower definition and define the NAIRU as the unemployment rate that is consistent with inflation converging to the rate of long-term aggrandizement expectations in the economy. This approach has proven useful for modelling inflation. Other approaches to estimating the NAIRU (or total employment) are intuitively appealing but less useful for modelling inflation. For case, the NAIRU can exist modelled as a function of appreciable variables like labour market regulation (e.g. minimum wages), marriage membership rates, the level of unemployment benefits, and demographics. Another approach defines full employment using types of unemployment, which can exist linked to appreciable characteristics. Full employment occurs when at that place is no cyclical unemployment, and the but unemployment is either structural or frictional (e.g. Ballantyne et al 2014). Models can include labour marketplace dynamics such as longer durations of unemployment leading to skills cloudburst and decreased employability (eastward.g. Brawl 2009). Some researchers connect the NAIRU to the rates at which employees observe and get out jobs (east.g. Dickens 2009). These other methods tin can be used for exploring the economics of why the NAIRU might alter. However, the method in this article aims only to detect changes in the NAIRU, not explicate them.

Estimating the NAIRU

The NAIRU is not observable, but we can infer it from the relationship between the unemployment rate and inflation (or wage growth). In this article, the NAIRU is the unemployment rate at which inflation converges to the level of long-run inflation expectations. If the NAIRU was constant over fourth dimension, it could be estimated using a unproblematic regression of inflation against the unemployment rate.[2] Even so, prove suggests that the NAIRU changes over time and models that allow the NAIRU to vary generally take greater predictive power for inflation and wage growth (e.1000. Gruen et al 1999; Ball and Mankiw 2002).

To estimate a NAIRU that varies over time requires a more complex model. Aggrandizement and wage growth are affected by the unemployment gap (amidst other things). The gap cannot be observed direct, just the relationship between the unemployment gap and inflation means we are able to infer changes in the gap by observing aggrandizement outcomes, decision-making for other things. More concretely, if inflation is lower than expected, a possible explanation is that the unemployment gap was larger than we thought. In response, we might lower our guess of the NAIRU. Nosotros use a statistical technique known as the Kalman filter to calculate how much nosotros should revise our estimate of the NAIRU based on new data. For example, our model suggests we should increase our guess of the NAIRU by just over ¼ of a percentage point in response to quarterly inflation existence ½ percentage indicate higher than expected in that quarter.

The unemployment gap also affects wage growth. Conceptually, the NAIRU should be the same whether we use inflation or wage growth to estimate it. Nonetheless, in do, the estimate varies if you apply inflation or use wage growth (e.yard. Gruen et al 1999 and Ballantyne et al 2014). The method used here derives a unmarried estimate of the NAIRU using information from both inflation and wage growth.

The model

The model comprises separate equations for aggrandizement, wage growth and the NAIRU. Inflation and wage growth are modelled using lags of themselves and each other, long-term inflation expectations, the unemployment gap, the change in the unemployment rate, and import prices (more details in Appendix A). Oil prices appear in both equations, but only prior to 1977 when they were correlated with large changes in prices and wages.[3] Inflation is measured past quarterly trimmed mean inflation. Wage growth is measured by growth in unit labour costs (ULCs), defined as average earnings growth adjusted for productivity growth. Strictly speaking, the ULC measure used here includes more than but wages. Past incorporating productivity as well, information technology becomes more than relevant for aggrandizement forecasting. The model as well includes an equation for the evolution of the unobservable NAIRU. We do not model the structural determinants of the NAIRU. The baseline assumption is that it will stay constant in the next menstruation.

The NAIRU estimates

Fundamental estimates of the NAIRU from the model, as well equally the uncertainty effectually these estimates, are presented in Graph ii. The estimated NAIRU peaked in 1995 at just over 7 per cent of the labour force and has declined more than or less steadily since then to around 5 per cent in early on 2017. While the structural determinants of the NAIRU are not modelled here, other research has attempted to explain changes in the NAIRU. The results of that research are far from conclusive, but OECD studies provide some possible explanations.[four] Those studies suggest that the increase in unemployment benefits as a share of average wages from the mid 1970s to the early 1990s, and their subsequent decline, influenced the ascent and fall in the NAIRU. Decreases in trade union membership and product market regulation are too estimated to have lowered the NAIRU since the mid 1990s. The studies did not find any prove that the level of the minimum wage affected the NAIRU.

Graph 2

Graph 2 NAIRU Estimate

Economic conditions may also have delayed effects on the NAIRU. Long periods of unemployment can decrease an private's hereafter employment opportunities, possibly because of existent or perceived skills compunction. These long periods out of work tend to occur more than ofttimes when the unemployment rate is loftier. This process – known every bit hysteresis – tin can raise structural unemployment and often follows rapid increases in the unemployment rate during recessions. When the labour market is tight, employers are more probable to hire workers with less desirable work histories or characteristics. A period of employment often improves a person's future chore prospects, which may lower structural unemployment. In Australia, the rise in the estimated NAIRU between 1984 and 1995 occurred aslope ii recessions. Conversely, the fall in the NAIRU over the past 20 years has occurred during a prolonged period of economic growth.

We can use the primal estimates of the NAIRU to construct estimates of the unemployment gap. The relatively smooth evolution of the estimated NAIRU through time suggests that nearly of the curt-term variation in the unemployment gap comes from observable changes in the unemployment rate.[5] It also suggests that movements in the NAIRU have been driven by tiresome-moving structural features of the labour market, which are typically difficult to observe.

The relationship betwixt the estimated unemployment gap and aggrandizement, relative to long-run expectations, is shown in Graph 3. As expected, aggrandizement tends to be higher when the unemployment gap is negative (i.east. when the observed unemployment rate is beneath the NAIRU). Similarly, wage growth tends to exist higher when the unemployment gap is negative. Both relationships are nonlinear, so increases in the unemployment gap have less of an effect on aggrandizement and wage growth equally the unemployment gap increases. If there are already many unemployed workers looking for a task, a few more than are unlikely to have much issue on the wage offered.

Graph 3

Graph 3 Inflation, ULC Growth and Unemployment

NAIRU estimates are uncertain, specially in existent time

Estimates of the NAIRU are uncertain because it cannot be observed and the data provide just a noisy point. The current guess of the NAIRU is five.0 per cent of the labour strength, with a 70 per cent confidence interval of plus or minus i percentage point. This means that, even if the models of inflation and wage growth are correct, in that location is still a 30 per cent chance that the 'true' unobserved NAIRU is either higher than 6 per cent or lower than 4 per cent (Graph two). Given the March quarter unemployment charge per unit of five¾ per cent, the model suggests an 80 per cent take a chance that the unemployment charge per unit is higher up the NAIRU.

The central estimates of the NAIRU presented in Graph 2 use the full history of the data. However, the path of the NAIRU estimated now tin look quite different to the path estimated at various times in the past, even using the same model and information history. The high degree of doubt effectually the NAIRU estimates means new data can change the judge of the NAIRU for the previous few years. Graph 4 shows how the revisions to the NAIRU estimate have unfolded over time.[vi] Each series shows the NAIRU approximate based on the data upwards to that time period. For example, the estimates made using data up to the December quarter of 2015 showed the NAIRU had been adequately flat over the previous 2 years and was around 5.2 per cent. But past the March quarter of 2017, the latest estimates show the NAIRU had been falling over that same menses and was v.0 per cent in the March quarter of 2015.

Graph four

Graph 4 Revisions to NAIRU Estimates

When updating the economic forecasts each quarter, Bank staff employ the latest estimate of the NAIRU as an input into the forecasts for inflation and wage growth. Because of the incertitude around the NAIRU, the estimates generated by incorporating new data each quarter can move effectually much more sharply than the estimates made with the do good of hindsight and the total history of the data. Graph 5 shows estimates of the NAIRU through time that use but the data available up to that fourth dimension period, compared with estimates that use the full information history. The real-time serial shows the estimate of the NAIRU the model would have made for each quarter at that time. These real-time estimates requite a ameliorate sense of the uncertainty faced by forecasters than the estimates using the full history.[7]

Graph 5

Graph 5 Evolution of NAIRU Estimates

Inflation expectations and the NAIRU

In the model, the unemployment gap drives deviations of inflation and wage growth from long-term inflation expectations. This ways that estimated movements in the NAIRU depend on which mensurate of inflation expectations is used. Previous versions of the model used inflation expectations derived from 10-yr bond rates. Moore (2016) examines a wide range of measures of inflation expectations available in Australia. Expectations measures derived from bond rates do non purely reflect inflation expectations because they also include adventure and liquidity premia. Each measure has pros and cons, so in this model we combine a range of measures of inflation expectations (Graph 6). Specifically, we extract a mutual signal of long-term expectations from the various measures after controlling for each measure'southward co-motion with contempo aggrandizement.[8]

Graph 6

Graph 6 Inflation Expectations

The boilerplate level of the inflation expectations measure used in the model also affects the level of the NAIRU estimates. Many of the measures of inflation expectations appear to be upwardly biased (as tends to exist the case for other economies), which would issue in a downward bias in the NAIRU estimate. To avoid this problem, nosotros adjust the mean of the estimated inflation expectations serial to match the mean of aggrandizement since 1996, which is roughly the catamenia when expectations appear to take been anchored effectually the aggrandizement target.

The NAIRU and Recent Weakness in Wage Growth

Our model of inflation and wage growth accounts for the effects of a number of appreciable variables. However, there are other variables that tin bear upon inflation and wage growth that are not included in the model (for case, because of insufficient data). If these omitted variables change and cause inflation or wage growth to deviate from the model predictions, some of this deviation will be attributed to changes in the NAIRU. Therefore the model'south guess of the NAIRU could change, fifty-fifty though the 'true' unobservable NAIRU might not have.

Recent RBA work has considered some possible explanations for low wage growth that do not represent to variables in the model.[nine] Decreased bargaining ability of labour and relatively loftier underemployment are two of the explanations canvassed. We wait at how these explanations could touch on model estimates of the NAIRU.

Decreased employee bargaining power

If employees have less bargaining power, then 1 would expect to run into lower wage growth (all else equal). Because bargaining ability is not in the model, wage growth would exist lower than predicted and the NAIRU estimate would fall. If a reduction in bargaining power is sustained, the NAIRU approximate would continue to fall. A permanent decrease in bargaining power would lead the NAIRU to decline to a lower level reflecting decreased wage pressures at whatsoever given unemployment rate. Even so, if bargaining power were to increase later on a temporary reduction, wage growth would kickoff surprising the model on the upside and the guess of the NAIRU would increment again.

Bargaining power is not an appreciable variable. This means that the model cannot tell us whether any given change in the NAIRU is caused by a change in bargaining power. The model deals with this past treating all unmodelled changes in wage growth the same way. It estimates how much of each change is temporary versus how much is permanent, based on historical experience.

Relatively more underemployment

The underemployment rate measures the number of employed people who would like, and are available, to piece of work additional hours, expressed equally a share of the labour forcefulness (Graph seven).

Graph vii

Graph 7 Labour Underutilisation

The model in this article does not include the underemployment rate, but it does include the unemployment rate.[x]

Betwixt 2004 and 2014, the underemployment rate tended to movement adequately closely with the unemployment rate. This meant the unemployment rate was a reasonable proxy for any effect that changes in the underemployment rate had on wage growth. Over the past few years, notwithstanding, the underemployment charge per unit has been relatively stable while the unemployment charge per unit has declined. Whatever effect of the underemployment rate on wage growth – over and above the effect of the unemployment rate – would consequence in lower wage growth than expected by the model. This would so cause the model'south estimate of the NAIRU to decline. This explanation implies that the unemployment gap, every bit measured using the unemployment rate, is currently understating the caste of spare chapters in the labour market. The model estimate of the NAIRU is then revised down to get a larger unemployment gap.

Conclusion

Estimates of the NAIRU are an input into the Bank's aggrandizement and wage forecasts, which in turn feed into monetary policy decisions. The model-based estimates of the NAIRU presented in this article exercise non rely directly on structural features of the labour market, but are inferred from departures from the expected relationship between unemployment and inflation or wage growth. There is substantial incertitude around these estimates of the NAIRU, particularly in existent time. This doubtfulness means that the model's guess of the NAIRU tin can modify quite a scrap from quarter to quarter as new data become available, even though nosotros think the 'true' unobserved NAIRU actually evolves quite slowly.

Appendix A: Estimating the Model

The model comprises equations for inflation and wage growth as well every bit for the NAIRU. Details of the variables used are in Table A1.

We estimate the model by maximum likelihood using the Kalman filter. Given the parameters, and an initial value for the NAIRU in 1968, the Kalman filter generates estimates of the NAIRU based on the data available up to each fourth dimension period. The NAIRU is then projected forrard ane catamenia (every bit per Equation (A3)). Forth with the observable variables, this generates a prediction for aggrandizement and wage growth for the flow alee (as per Equations (A1) and (A2)). Any difference between the prediction and the bodily information volition cause some revision to the NAIRU approximate for that quarter. The procedure is and then repeated for the next quarter.

Stepping through the quarters gives a series of prediction errors, which depend on the parameter values. The maximum likelihood interpretation routine finds the parameters that minimise those errors and give the best fit to the inflation and wage growth information. The results of interpretation are in Table A2.

A statistical smoothing method is then used to construct the estimates based on the full history of the data. The smoothing method steps backward in time from the electric current period, updating the existent-time NAIRU estimates in calorie-free of more recent data.

Tabular array A2: Parameter Estimates

Estimation sample is March 1968 to March 2017

Inflation equation ULC growth equation
Coefficient(a) Standard error Coefficient(a) Standard error
Inline Equation 0.35*** 0.06 0.45** 0.22
Δpt −1 0.24*** 0.06 0.47** 0.22
Δpt −2 0.xvi*** 0.05 0.09 0 .16
Δpt −3 0.18*** 0.06
Δulct −1 0.06*** 0.02
Inline Equation −0.seventy 0.53 −5.6*** 1. 7
Inline Equation −0.38*** 0 .10 −one.nine*** 0.53
Inline Equation 0.004 0.006
Δoilt −2 (b) 0.02*** 0.01 0.05*** 0.01
σ measurement (c) 0.30*** 0.02 1.17*** 0.06
NAIRU equation
Coefficient(a) Standard fault
σ NAIRU (c) 0.xl*** 0.thirteen

(a) *, ** and *** announce P values less than 0.one, 0.05 and 0.01 respectively
(b) Prior to 1977 only
(c) Standard difference estimates, the errors are assumed to be distributed unremarkably with mean zero and variance σ ii

Source: RBA

References

Brawl L (2009), 'Hysteresis in Unemployment: Quondam and New Testify', NBER Working Paper No 14818.

Ball 50 and M Mankiw (2002), 'The NAIRU in Theory and Practice', Journal of Economic Perspectives, 16(iv), pp 115–136.

Ballantyne A, D De Voss and D Jacobs (2014), 'Unemployment and Spare Capacity in the Labour Market', RBA Bulletin, September, pp 7–twenty.

Bassanini A and R Duval (2006), 'Employment Patterns in OECD Countries: Reassessing the Role of Policies and Institutions', OECD Social, Employment and Migration Working Papers No 35.

Bishop J and Northward Cassidy (2017), 'Insights into Low Wage Growth in Australia', RBA Bulletin, March pp 13–xx.

Chan J, T Clark and 1000 Koop (2015), 'A New Model of Inflation, Trend Inflation, and Long-Run Inflation Expectations', Federal Reserve Bank of Cleveland Working Newspaper No 15–20.

Davis Yard, M McCarthy and J Bridges (2016), 'The Labour Market during and after the Terms of Merchandise Boom', RBA Bulletin, March, pp 1–10.

Dickens W (2009), 'Has the Recession Increased the NAIRU?', Brookings Study.

Gianella C, I Koske, E Rusticelli and O Chatal (2008), 'What Drives the NAIRU? Prove from a Panel of OECD Countries', OECD Economics Department Working Papers No 649.

Gruen D, A Pagan and C Thompson (1999), 'The Phillips Bend in Australia', RBA Inquiry Give-and-take Newspaper 1999-01.

Kozicki Southward and P Tinsley (2012), 'Effective Use of Survey Information in Estimating the Evolution of Expected Inflation', Journal of Money, Credit and Cyberbanking, 44(1), pp 145–169.

Lowe P (2016), 'Inflation and Budgetary Policy', Accost to Citi's eighth Annual Australian & New Zealand Investment Conference, Sydney, xviii Oct.

Moore A (2016), 'Measures of Inflation Expectations in Commonwealth of australia', RBA Message, Dec, pp 23–31.