| Party |
| Modified aggregation | Deviations from strict proportionality (power―seats) |
| CDU/CSU | seats (rel.) | 0.52482205 |
|
|
| ex ante | 0.501040618 | −0.023781432 |
|
| ex post | 0.429696945 | −0.095125105 |
| SPD | seats (rel.) | 0.435363492 |
|
|
| ex ante | 0.301324545 | −0.134038947 |
|
| ex post | 0.254545455 | −0.180818037 |
| FDP | seats (rel.) | 0.111550297 |
|
|
| ex ante | 0.242562455 | 0.131012158 |
|
| ex post | 0.395151491 | 0.283601194 |
| Grüne (since 1983) | seats (rel.) | 0.070312448 |
|
|
| ex ante | 0.153269967 | 0.082957519 |
|
| ex post | 0.116666667 | 0.046354219 |
| PDS/ | seats (rel.) | 0.055674471 |
|
| Linkspartei.PDS/ | ex ante | 0.072640727 | 0.016966256 |
| Die Linke (since 1991) | ex post | 0.000000000 | −0.055674471 |
| Others | seats (rel.) | 0.01402697 |
|
| (1949-61) | ex ante | 0.01501596 | 0.00098899 |
|
| ex post | 0.01301044 | −0.00101653 |