Table 1. Prediction accuracy obtained by different methods for total energy consumption (unit: 104 tons of SCE).
| Year | Actual | Original GM(1,1) | MLPGM(1,1) | GPGM(1,1) | GARGM(1,1) | ||||
|---|---|---|---|---|---|---|---|---|---|
| Predicted | APE | Predicted | APE | Predicted | APE | Predicted | APE | ||
| 1990 | 98703 | 98703 | 0 | 98703 | 0 | 98703 | 0 | 98703 | 0 |
| 1991 | 103783 | 108706.1 | 4.74 | 103783 | 0 | 103783 | 0 | 101195.7 | 2.49 |
| 1992 | 109170 | 112335.5 | 2.9 | 116225.8 | 6.46 | 108445.2 | 0.66 | 102596.3 | 3.14 |
| 1993 | 115993 | 116086.1 | 0.08 | 111804.1 | 3.61 | 111804.1 | 3.61 | 117195.8 | 1.04 |
| 1994 | 122737 | 119962 | 2.26 | 115248.8 | 6.10 | 124675.1 | 1.58 | 121997.9 | 0.60 |
| 1995 | 131176 | 123967.2 | 5.50 | 129154.8 | 1.54 | 129154.8 | 1.54 | 127012.8 | 3.17 |
| 1996 | 138948 | 128106.2 | 7.80 | 133816.1 | 3.69 | 133816.1 | 3.69 | 132251.6 | 4.82 |
| 1997 | 137798 | 132383.3 | 3.93 | 138668.2 | 0.63 | 138668.2 | 0.63 | 137725.9 | 0.05 |
| 1998 | 132214 | 136803.3 | 3.47 | 143721 | 8.7 | 129885.5 | 1.76 | 129692.7 | 1.91 |
| 1999 | 133831 | 141370.8 | 5.63 | 133756.5 | 0.06 | 133756.5 | 0.06 | 134280.7 | 0.34 |
| 2000 | 138553 | 146090.8 | 5.44 | 137709.8 | 0.61 | 137709.8 | 0.61 | 139002.5 | 0.32 |
| 2001 | 143199 | 150968.4 | 5.43 | 141743.6 | 1.02 | 141743.6 | 1.02 | 143858.7 | 0.46 |
| 2002 | 151797 | 156008.9 | 2.77 | 145855.2 | 3.91 | 145855.2 | 3.91 | 148849.8 | 1.94 |
| 2003 | 174990 | 161217.6 | 7.87 | 150041.6 | 14.26 | 172393.5 | 1.48 | 176275.6 | 0.73 |
| MAPE | 4.13 | 3.61 | 2.59 | 1.50 | |||||
| 2004 | 203227 | 166600.2 | 18.02 | 178901.5 | 11.97 | 178901.5 | 11.97 | 183797.7 | 9.56 |
| 2005 | 224682 | 172162.6 | 23.37 | 185702.4 | 17.35 | 185702.4 | 17.35 | 191681.9 | 14.69 |
| 2006 | 264270 | 177910.7 | 32.68 | 192813.8 | 27.04 | 192813.8 | 27.04 | 199949.4 | 24.34 |
| 2007 | 265583 | 183850.7 | 30.77 | 200254.3 | 24.60 | 200254.3 | 24.60 | 208623.1 | 21.45 |
| MAPE | 26.21 | 20.23 | 20.23 | 17.51 | |||||