Forecasts in Times of Crises

Transcription

1 Forecasts n Tmes of Crses Aprl 2017 Chars Chrstofdes IMF Davd J. Kuenzel Wesleyan Unversty Theo S. Echer Unversty of Washngton Chrs Papageorgou IMF 1

2 Macroeconomc forecasts suffer from three sources of uncertanty: 1. Model uncertanty 2. Parameter uncertanty 3. Data uncertanty Plus: Forecastng ssues are compounded durng tmes of crses, whch s exactly when polcy makers need qualty forecasts How do IMF crss forecasts actually stack up? We address ths queston n the context of IMF forecasts for program countres 2

3 Basc approach: We evaluate IMF forecasts based on macroeconomc denttes. Why? Elmnates model and parameter uncertanty Contrbutons of our paper: 1. We decompose IMF forecast errors n crss countres nto systematc and unsystematc components 2. We dentfy to what extent forecast errors of key macroeconomc aggregates are drven by specfc subcomponents 3. We consder a wde range of macro denttes that are key n crss countres: GDP, current account, fnancal account, gov. expendture, gov. revenue 3

4 Forecastng Based on Macroeconomc Identtes 4

5 Our focus s on: Macroeconomc denttes at the core of IMF programs Growth rates of nomnal varables Example Decomposton of GDP growth: where σ y,j represents the elastcty of GDP growth wth respect to the growth rate n a subcomponent j Smlar approach for other denttes: current account, fnancal account, gov. expendtures, and gov. revenues m x c c y m y x y g y p y g c y p c y g p g p,,,,,, 5

6 Evaluatng IMF Forecasts 6

7 To evaluate forecasts, we use a symmetrc loss functon postve and negatve forecast errors are penalzed equally Two-pronged approach for forecast evaluaton: 1. Mean squared error (MSE) decomposton nto systematc and unsystematc forecast errors 2. Absolute error (AE) regresson analyss of macroeconomc denttes 7

8 Let x be the forecasted growth rate of varable x, whle x s the actually realzed growth rate. Forecast MSE of varable x s then: Bas + varance = systematc forecast error Covarance = unsystematc forecast error,.e. whte nose 1. Mean Squared Error (MSE) Decomposton x x x x N r x x N x x ˆ 2 ˆ ˆ / ˆ Bas Varance Covarance 8

9 2. Absolute Error Regressons Do forecast errors for subcomponents drve forecast errors for macroeconomc aggregates? For macroeconomc aggregate y wth S subcomponents, we run: yˆ y S j1 Coeffcent nterpretaton: 1% ncrease n mean absolute error (MAE) of x j causes a β j % change n the MAE of y j xˆ j x j where: N 1 MAE y yˆ y / N 9

10 Data for IMF Forecast Evaluaton Data for forecasts and actual realzaton comes from IMF s Montorng of Fund Arrangements (MONA) Database Program country data: Broadest sample: 170 countres Forecast data: Predctons for frst program year from ntal IMF revew Realzed data: Actual observatons as noted n fnal IMF program revew 10

11 Results: Decomposton and Determnants of IMF Forecast Errors 11

12 Number of Crss Countres GDP Growth Forecast Errors NGDP forecast error (n %) GDP growth forecasts are, on average, unbased n the global sample 12

13 GDP Growth Forecasts: Bas and MSE Decomposton Varables Mean Forecast Bas (n %) 1a 1b 1c 1d 1e 1f 1g 1h 1 1j 1k 1l All LIC Non-LIC All LIC Non- LIC Contrbuton to Varable's Forecast MS E (n %) Bas Varance Covarance All LIC Non- LIC All LIC Non- LIC GDP Growth ** 1.1* Prvate Consumpton Growth * Publc Consumpton Growth Import Growth Export Growth -2.6** ** Publc Investment Growth 8.6*** 8.7*** 8.6** Prvate Investment Growth Observatons BUT: downward bas n LIC sample and upward bas n Non-LIC sample for GDP growth Export and publc nvestment growth are the only GDP subcomponents wth bas GDP growth and subcomponent MSEs are mostly drven by unsystematc errors,.e. whte nose 13

14 Contrbutors to GDP Growth Forecast Errors Varables wth sgnfcant bases (publc nvestment growth, export growth) do not drve forecast errors n GDP growth What matters nstead? Predcton errors n consumpton growth Why? Consumpton = largest GDP contrbutor Dependent varable: GDP growth 2a 2b 2c (Absolute Error, AE) All LICs Non-LICs Prvate Consumpton Growth 0.202*** 0.247*** 0.144* (AE) (0.064) (0.092) (0.074) Publc Consumpton Growth (AE) (0.054) (0.068) (0.078) Import Growth (AE) (0.053) (0.065) (0.093) Export Growth (AE) (0.047) (0.055) (0.057) Publc Investment Growth (AE) (0.016) (0.019) (0.021) Prvate Investment Growth *** (AE) (0.021) (0.024) (0.026) Constant 0.018*** 0.019*** (0.005) (0.006) (0.008) Observatons R-squared

15 Current Account Growth Forecasts: Bas and MSE Decomposton Mean Forecast Bas (n %) Contrbuton to Varable's Forecast MS E (n %) Bas Varance Covarance 3a 3b 3c 3d 3e 3f 3g 3h 3 3j 3k 3l Varables All LIC Non-LIC All LIC Non-LIC All LIC Non-LIC All LIC Non-LIC Current Account Growth Goods Import Growth Goods Export Growth -3.7** -4.1** S ervces Import Growth -3.0** S ervces Export Growth -3.9** -4.8* Net Transfers Growth -10.7** *** Net Income Growth Observatons Although not sgnfcant, mean forecast of CA growth shows substantal upward bas CA forecast errors are drven by systematc varance predcton errors Most CA subcomponent forecasts suffer from sgnfcant downward bas (due to LICs) 15

16 Contrbutors to Current Account Growth Forecast Errors None of the subcomponents are sgnfcant contrbutors to forecast errors n CA growth tself Why? Most lkely due to pronounced varance msmatches n CA growth forecasts Panel A: Current Account Balance Dep. varable: CA growth 4a 4b 4c (Absolute Error, AE) All LICs Non-LICs Goods Import Growth (AE) (4.671) (7.292) (1.010) Goods Export Growth (AE) (3.922) (4.792) (1.435) S ervces Import Growth (AE) (4.428) (5.666) (0.879) S ervces Export Growth (AE) (1.849) (1.703) (1.142) Net Transfers Growth ** (AE) (0.636) (1.033) (0.202) Net Income Growth (AE) (0.443) (0.577) (0.343) Constant 2.395* (1.359) (2.192) (0.208) Observatons R-squared

17 Fnancal Account Growth Forecasts: Bas and MSE Decomposton Mean Forecast Bas (n %) Contrbuton to Varable's Forecast MS E (n %) Bas Varance Covarance 3m 3n 3o 3p 3q 3r 3s 3t 3u 3v 3w 3x Varables All LIC Non-LIC All LIC Non-LIC All LIC Non-LIC All LIC Non-LIC Fnancal Account Growth Net Drect Investment Reserve Assets Other Investment Net Portfolo Investment Observatons Although not sgnfcant, mean forecast of FA growth shows substantal downward bas Growth forecasts for nearly all FA components ndcate systematc falure at capturng the varance of fnancal flows 17

18 Contrbutors to Fnancal Account Growth Forecast Errors Smlar to the current account, none of the subcomponents s a sgnfcant contrbutor to forecast errors n FA growth Lack of sgnfcant results s agan most lkely due to systematc varance msmatches n fnancal flow forecasts Our fndngs ndcate that the IMF s BoP forecastng approach mght requre a realgnment Panel B: Fnancal Account Balance Dep. varable: FA growth 4d 4e 4f (Absolute Error, AE) All LICs Non-LICs Net Drect Investment Growth (AE) (0.428) (0.574) (0.579) Reserve Assets Growth (AE) (0.041) (0.056) (0.061) Other Investment Growth * (AE) (0.008) (0.028) (0.010) Net Portfolo Investment Growth (AE) (0.059) (0.146) (0.109) Constant 1.499*** 1.665** 1.290** (0.438) (0.669) (0.538) Observatons R-squared

19 Fscal Budget Forecasts Summary Growth n government revenues and expendtures are, on average, forecasted wthout bas Only two subcomponents are forecasted wth bas: nterest expendtures (upward bas), tax revenue (downward bas) Fscal revenue and expendture forecasts are mostly subject to unsystematc errors Forecast errors for non-nterest and captal expendtures drve predcton errors for government spendng Forecast errors for tax revenues drve fscal revenue forecast errors 19

20 Polcy Implcatons 20

21 IMF crss forecasts of key macroeconomc aggregates are unbased, n partcular GDP growth Good news for credblty of IMF program procedures But analyss shows sgnfcant heterogenety between LICs and Non-LICs Areas n need of mprovements: Subcomponents of BoP are forecasted wth substantal bas Current and fnancal account forecasts suffer from systematc varance msmatches Systematc errors n IMF forecasts are more prevalent for LICs 21