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| Factor | Mean | ||||
|---|---|---|---|---|---|
| 2000 | 2003 | 2007 | 2010 | 2013 | |
| DI1 | 2112 | 2122 | 2278 | 2501 | 2747 |
| DI2 | 998 | 999 | 1003 | 1021 | 1030 |
| UI1 | 83 | 84 | 81 | 82 | 84 |
| DO1 | 364 | 389 | 352 | 385 | 445 |
| DO2 | 121 | 141 | 115 | 124 | 136 |
| DO3 | 428 | 750 | 619 | 647 | 733 |
| UO1 | 24 | 34 | 23 | 26 | 28 |
