A6.24 Discounting is solely concerned with adjusting for social time preference and has nothing to do with adjusting for inflation. The recommended Green Book discount rate applies to real values, with the effects of general inflation already removed. To promote transparency the best practice approach is to first convert costs or benefits to a real price basis, and then perform the discounting adjustment. The inflation rate and discount rate should not be added and applied to costs and benefits, as it gives an arithmetically incorrect result.
Table 9. Standard Discount Rates and Associated Discount Factors
Year | Discount Rate | Discount | Year | Discount | Rate |
0 |
| 1 | 31 | 3.000% | 0.3459 |
1 | 3.500% | 0.9662 | 32 | 3.000% | 0.3358 |
2 | 3.500% | 0.9335 | 33 | 3.000% | 0.3260 |
3 | 3.500% | 0.9019 | 34 | 3.000% | 0.3165 |
4 | 3.500% | 0.8714 | 35 | 3.000% | 0.3073 |
5 | 3.500% | 0.8420 | 36 | 3.000% | 0.2984 |
6 | 3.500% | 0.8135 | 37 | 3.000% | 0.2897 |
7 | 3.500% | 0.7860 | 38 | 3.000% | 0.2812 |
8 | 3.500% | 0.7594 | 39 | 3.000% | 0.2731 |
9 | 3.500% | 0.7337 | 40 | 3.000% | 0.2651 |
10 | 3.500% | 0.7089 | 41 | 3.000% | 0.2574 |
11 | 3.500% | 0.6849 | 42 | 3.000% | 0.2499 |
12 | 3.500% | 0.6618 | 43 | 3.000% | 0.2426 |
13 | 3.500% | 0.6394 | 44 | 3.000% | 0.2355 |
14 | 3.500% | 0.6178 | 45 | 3.000% | 0.2287 |
15 | 3.500% | 0.5969 | 46 | 3.000% | 0.2220 |
16 | 3.500% | 0.5767 | 47 | 3.000% | 0.2156 |
17 | 3.500% | 0.5572 | 48 | 3.000% | 0.2093 |
18 | 3.500% | 0.5384 | 49 | 3.000% | 0.2032 |
19 | 3.500% | 0.5202 | 50 | 3.000% | 0.1973 |
20 | 3.500% | 0.5026 | 51 | 3.000% | 0.1915 |
21 | 3.500% | 0.4856 | 52 | 3.000% | 0.1859 |
22 | 3.500% | 0.4692 | 53 | 3.000% | 0.1805 |
23 | 3.500% | 0.4533 | 54 | 3.000% | 0.1753 |
24 | 3.500% | 0.4380 | 55 | 3.000% | 0.1702 |
25 | 3.500% | 0.4231 | 56 | 3.000% | 0.1652 |
26 | 3.500% | 0.4088 | 57 | 3.000% | 0.1604 |
27 | 3.500% | 0.3950 | 58 | 3.000% | 0.1557 |
28 | 3.500% | 0.3817 | 59 | 3.000% | 0.1512 |
29 | 3.500% | 0.3687 | 60 | 3.000% | 0.1468 |
30 | 3.500% | 0.3563 | 61 | 3.000% | 0.1425 |
Table 10. Health Discount Rates and Associated Discount Factors
Year | Health Discount Rate | Health Discount Factor | Year | Health Discount Rate | Health Discount Factor |
0 |
| 1 | 31 | 1.286% | 0.6316 |
1 | 1.500% | 0.9852 | 32 | 1.286% | 0.6236 |
2 | 1.500% | 0.9707 | 33 | 1.286% | 0.6157 |
3 | 1.500% | 0.9563 | 34 | 1.286% | 0.6079 |
4 | 1.500% | 0.9422 | 35 | 1.286% | 0.6002 |
5 | 1.500% | 0.9283 | 36 | 1.286% | 0.5926 |
6 | 1.500% | 0.9145 | 37 | 1.286% | 0.5850 |
7 | 1.500% | 0.9010 | 38 | 1.286% | 0.5776 |
8 | 1.500% | 0.8877 | 39 | 1.286% | 0.5703 |
9 | 1.500% | 0.8746 | 40 | 1.286% | 0.5630 |
10 | 1.500% | 0.8617 | 41 | 1.286% | 0.5559 |
11 | 1.500% | 0.8489 | 42 | 1.286% | 0.5488 |
12 | 1.500% | 0.8364 | 43 | 1.286% | 0.5419 |
13 | 1.500% | 0.8240 | 44 | 1.286% | 0.5350 |
14 | 1.500% | 0.8118 | 45 | 1.286% | 0.5282 |
15 | 1.500% | 0.7999 | 46 | 1.286% | 0.5215 |
16 | 1.500% | 0.7880 | 47 | 1.286% | 0.5149 |
17 | 1.500% | 0.7764 | 48 | 1.286% | 0.5083 |
18 | 1.500% | 0.7649 | 49 | 1.286% | 0.5019 |
19 | 1.500% | 0.7536 | 50 | 1.286% | 0.4955 |
20 | 1.500% | 0.7425 | 51 | 1.286% | 0.4892 |
21 | 1.500% | 0.7315 | 52 | 1.286% | 0.4830 |
22 | 1.500% | 0.7207 | 53 | 1.286% | 0.4769 |
23 | 1.500% | 0.7100 | 54 | 1.286% | 0.4708 |
24 | 1.500% | 0.6995 | 55 | 1.286% | 0.4649 |
25 | 1.500% | 0.6892 | 56 | 1.286% | 0.4590 |
26 | 1.500% | 0.6790 | 57 | 1.286% | 0.4531 |
27 | 1.500% | 0.6690 | 58 | 1.286% | 0.4474 |
28 | 1.500% | 0.6591 | 59 | 1.286% | 0.4417 |
29 | 1.500% | 0.6494 | 60 | 1.286% | 0.4361 |
30 | 1.500% | 0.6398 | 61 | 1.286% | 0.4306 |