Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Election year | # of\nconstituency votes | # of\nparty list votes | % of\nparty list votes | # of\noverall seats won | +/– |
| --- | --- | --- | --- | --- | --- |
| 1949 |  | 6,934,975 | 29.2 | 131 / 402 |  |
| 1953 | 8,131,257 | 7,944,943 | 28.8 | 162 / 509 | 22 |
| 1957 | 11,975,400 | 11,875,339 | 39.7 | 181 / 519 | 19 |
| 1961 | 11,672,057 | 11,427,355 | 36.2 | 203 / 521 | 22 |
| 1965 | 12,998,474 | 12,813,186 | 39.3 | 217 / 518 | 14 |
| 1969 | 14,402,374 | 14,065,716 | 42.7 | 237 / 518 | 20 |
| 1972 | 18,228,239 | 17,175,169 | 45.8 | 242 / 518 | 5 |
| 1976 | 16,471,321 | 16,099,019 | 42.6 | 224 / 518 | 18 |
| 1980 | 16,808,861 | 16,260,677 | 42.9 | 218 / 497 | 6 |
| 1983 | 15,686,033 | 14,865,807 | 38.2 | 193 / 498 | 25 |
| 1987 | 14,787,953 | 14,025,763 | 37.0 | 186 / 497 | 7 |
| 1990 | 16,279,980 | 15,545,366 | 33.5 | 239 / 662 | 53 |
| 1994 | 17,966,813 | 17,140,354 | 36.4 | 252 / 672 | 13 |
| 1998 | 21,535,893 | 20,181,269 | 40.9 | 298 / 669 | 43 |
| 2002 | 20,059,967 | 18,484,560 | 38.5 | 251 / 603 | 47 |
| 2005 | 18,129,100 | 16,194,665 | 34.2 | 222 / 614 | 29 |
| 2009 | 12,077,437 | 9,988,843 | 23.0 | 146 / 620 | 76 |
| 2013 | 12,835,933 | 11,247,283 | 25.7 | 193 / 631 | 42 |
Question:
after 1949, how many consecutive years did the number of overall seats increase?
Answer:
6