メリット増減率別 メリット制適用状況の推移（継続事業・構成比）
| 計 | 減少 | 増加 | -45% | -40% | -35% | -30% | -25% | -20% | -15% | -10% | -5% | 0% | 5% | 10% | 15% | 20% | 25% | 30% | 35% | 40% | 45% | |
| 昭和48年度 | 40,406 | 73.8% | 22.3% | − | − | − | 43.5% | 8.7% | 7.5% | 6.3% | 5.5% | 2.3% | 3.9% | 1.9% | 3.0% | 2.4% | 2.0% | 1.7% | 11.4% | − | − | − |
| 昭和49年度 | 42,198 | 76.3% | 19.8% | − | − | − | 45.5% | 9.2% | 7.9% | 6.3% | 5.2% | 2.3% | 3.8% | 1.7% | 2.9% | 2.3% | 1.8% | 1.5% | 9.6% | − | − | − |
| 昭和50年度 | 44,013 | 81.1% | 15.6% | − | − | − | 51.4% | 9.3% | 7.6% | 6.1% | 4.8% | 1.9% | 3.3% | 1.5% | 2.4% | 1.9% | 1.4% | 1.2% | 7.2% | − | − | − |
| 昭和51年度 | 45,228 | 81.2% | 15.4% | − | − | 41.0% | 11.2% | 9.2% | 7.4% | 5.8% | 4.5% | 2.0% | 3.4% | 1.4% | 2.3% | 1.9% | 1.6% | 1.2% | 1.0% | 6.0% | − | − |
| 昭和52年度 | 46,334 | 80.0% | 16.6% | − | − | 41.2% | 10.6% | 8.7% | 7.0% | 5.8% | 4.7% | 1.9% | 3.3% | 1.4% | 2.5% | 1.9% | 1.6% | 1.2% | 1.1% | 6.9% | − | − |
| 昭和53年度 | 48,707 | 77.1% | 19.4% | − | − | 39.4% | 10.1% | 8.3% | 7.0% | 5.6% | 4.8% | 2.0% | 3.6% | 1.5% | 2.6% | 2.1% | 1.8% | 1.5% | 1.3% | 8.6% | − | − |
| 昭和54年度 | 49,070 | 75.4% | 21.0% | − | − | 38.5% | 10.1% | 7.8% | 6.6% | 5.6% | 4.7% | 2.1% | 3.6% | 1.4% | 2.8% | 2.3% | 2.0% | 1.6% | 1.3% | 9.5% | − | − |
| 昭和55年度 | 49,773 | 77.1% | 19.3% | − | 27.5% | 12.9% | 9.9% | 8.1% | 6.6% | 5.4% | 4.7% | 2.1% | 3.6% | 1.5% | 2.7% | 2.1% | 1.7% | 1.4% | 1.3% | 1.0% | 7.6% | − |
| 昭和56年度 | 51,074 | 78.0% | 18.6% | − | 28.5% | 12.9% | 10.2% | 8.1% | 6.5% | 5.3% | 4.6% | 2.0% | 3.4% | 1.4% | 2.5% | 2.1% | 1.8% | 1.4% | 1.2% | 1.0% | 7.1% | − |
| 昭和57年度 | 52,307 | 78.6% | 18.1% | − | 29.6% | 13.3% | 9.8% | 7.9% | 6.4% | 5.2% | 4.4% | 1.9% | 3.2% | 1.4% | 2.5% | 2.0% | 1.7% | 1.4% | 1.1% | 1.0% | 7.0% | − |
| 昭和58年度 | 55,403 | 77.7% | 19.0% | − | 30.2% | 13.0% | 9.6% | 7.7% | 6.2% | 5.1% | 4.2% | 1.8% | 3.3% | 1.3% | 2.6% | 2.1% | 1.7% | 1.5% | 1.3% | 1.1% | 7.5% | − |
| 昭和59年度 | 57,485 | 78.3% | 18.5% | − | 31.0% | 13.0% | 9.4% | 7.5% | 6.3% | 5.1% | 4.3% | 1.8% | 3.2% | 1.5% | 2.2% | 2.1% | 1.7% | 1.5% | 1.2% | 0.8% | 7.6% | − |
| 昭和60年度 | 58,580 | 79.4% | 17.6% | − | 32.3% | 13.2% | 9.7% | 7.6% | 6.0% | 4.9% | 4.1% | 1.8% | 3.0% | 1.3% | 2.3% | 1.8% | 1.6% | 1.3% | 1.2% | 1.0% | 7.1% | − |
| 昭和61年度 | 58,769 | 80.0% | 17.1% | − | 31.9% | 13.8% | 9.4% | 7.7% | 6.2% | 5.0% | 4.1% | 1.9% | 2.8% | 1.6% | 2.3% | 1.9% | 1.6% | 1.3% | 1.2% | 1.0% | 6.3% | − |
| 昭和62年度 | 61,730 | 80.5% | 16.6% | − | 33.3% | 13.5% | 9.6% | 7.6% | 5.8% | 4.8% | 4.0% | 1.7% | 2.9% | 1.3% | 2.2% | 1.7% | 1.5% | 1.3% | 1.1% | 0.9% | 6.6% | − |
| 昭和63年度 | 64,887 | 80.9% | 16.4% | − | 34.2% | 13.7% | 9.5% | 7.3% | 5.8% | 4.8% | 3.9% | 1.7% | 2.8% | 1.3% | 2.2% | 1.8% | 1.5% | 1.2% | 1.0% | 0.9% | 6.6% | − |
| 平成元年度 | 68,132 | 81.0% | 16.3% | − | 35.3% | 13.5% | 9.3% | 7.3% | 5.7% | 4.6% | 3.8% | 1.5% | 2.8% | 1.1% | 2.0% | 1.7% | 1.4% | 1.3% | 1.0% | 0.8% | 6.9% | − |
| 平成２年度 | 83,272 | 80.9% | 16.6% | − | 38.3% | 12.9% | 8.8% | 6.7% | 5.1% | 4.2% | 3.5% | 1.4% | 2.5% | 1.1% | 1.9% | 1.5% | 1.4% | 1.1% | 0.9% | 0.9% | 7.6% | − |
| 平成３年度 | 87,437 | 82.5% | 15.2% | − | 40.4% | 13.2% | 9.0% | 6.4% | 5.0% | 3.9% | 3.2% | 1.4% | 2.3% | 1.1% | 1.8% | 1.5% | 1.3% | 1.1% | 1.0% | 0.8% | 6.8% | − |
| 平成４年度 | 96,752 | 84.4% | 13.5% | − | 43.7% | 13.3% | 8.6% | 6.1% | 4.6% | 3.7% | 2.9% | 1.3% | 2.1% | 0.9% | 1.6% | 1.4% | 1.2% | 1.0% | 0.8% | 0.7% | 6.0% | − |
| 平成５年度 | 99,745 | 84.1% | 13.8% | − | 44.3% | 13.1% | 8.3% | 6.1% | 4.7% | 3.5% | 2.9% | 1.2% | 2.2% | 0.9% | 1.6% | 1.4% | 1.2% | 1.0% | 0.8% | 0.7% | 6.1% | − |
| 平成６年度 | 101,407 | 83.6% | 14.3% | − | 44.3% | 12.7% | 8.4% | 6.0% | 4.5% | 3.6% | 2.9% | 1.3% | 2.2% | 0.9% | 1.6% | 1.4% | 1.1% | 1.0% | 0.8% | 0.8% | 6.6% | − |
| 平成７年度 | 102,243 | 82.8% | 14.9% | − | 44.2% | 12.4% | 8.1% | 5.9% | 4.4% | 3.6% | 3.0% | 1.2% | 2.3% | 1.0% | 1.7% | 1.4% | 1.2% | 1.0% | 0.9% | 0.8% | 7.1% | − |
| 平成８年度 | 99,609 | 82.7% | 15.2% | − | 44.4% | 12.3% | 8.1% | 5.8% | 4.5% | 3.5% | 2.9% | 1.2% | 2.1% | 0.9% | 1.6% | 1.4% | 1.2% | 1.1% | 0.9% | 0.8% | 7.2% | − |
| 平成９年度 | 97,995 | 82.6% | 15.3% | 0.0% | 44.5% | 12.3% | 8.0% | 5.7% | 4.4% | 3.6% | 2.9% | 1.2% | 2.1% | 0.9% | 1.7% | 1.4% | 1.2% | 1.0% | 0.9% | 0.7% | 7.5% | 0.0% |
| 平成10年度 | 97,907 | 82.6% | 15.3% | 0.0% | 44.5% | 12.3% | 8.0% | 5.7% | 4.4% | 3.6% | 2.9% | 1.2% | 2.1% | 0.9% | 1.7% | 1.4% | 1.2% | 1.0% | 0.9% | 0.7% | 7.5% | 0.0% |
| 平成11年度 | 97,242 | 82.5% | 15.4% | 0.1% | 44.7% | 12.3% | 8.0% | 5.7% | 4.4% | 3.3% | 2.9% | 1.2% | 2.1% | 1.0% | 1.6% | 1.4% | 1.2% | 1.0% | 0.9% | 0.7% | 7.6% | 0.0% |
| 平成12年度 | 95,031 | 82.9% | 15.0% | 0.1% | 45.2% | 12.2% | 7.9% | 5.7% | 4.4% | 3.5% | 2.7% | 1.2% | 2.1% | 0.9% | 1.6% | 1.3% | 1.1% | 1.0% | 0.8% | 0.8% | 7.5% | 0.0% |
| 平成13年度 | 93,758 | 83.1% | 14.9% | 0.0% | 46.2% | 12.0% | 7.8% | 5.5% | 4.3% | 3.4% | 2.7% | 1.2% | 2.0% | 0.9% | 1.6% | 1.3% | 1.1% | 1.0% | 0.9% | 0.7% | 7.4% | 0.0% |
| 平成14年度 | 91,651 | 83.5% | 14.5% | 0.0% | 46.7% | 12.1% | 7.7% | 5.5% | 4.3% | 3.3% | 2.7% | 1.2% | 2.0% | 0.9% | 1.5% | 1.3% | 1.1% | 1.0% | 0.8% | 0.7% | 7.1% | 0.0% |