| Jahr | untere Grenze in Millionen | obere Grenze in Millionen |
|---|---|---|
| 1950 | 69,35 | 69,35 |
| 1960 | 73,15 | 73,15 |
| 1970 | 78,07 | 78,07 |
| 1980 | 78,40 | 78,40 |
| 1990 | 79,75 | 79,75 |
| 2000 | 82,26 | 82,26 |
| 2013 | 80,77 | 80,77 |
| 2020 | 81,43 | 81,95 |
| 2030 | 79,23 | 80,92 |
| 2040 | 75,96 | 78,91 |
| 2050 | 71,90 | 76,12 |
| 2060 | 67,56 | 73,08 |