what is the number of presidents who resigned?
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col : order in\nposition | president of\nthe republic | length of\nthe presidential\naction | rank by\nlength\nof term(s) | notes row 1 : 1 | k. j. ståhlberg | 5 years, 220 days | 8 | 1 term serving row 2 : 2 | lauri kristian relander | 6 years, 0 days\none leap year (1928) | 6 | 1 term serving row 3 : 3 | p. e. svinhufvud | 5 years, 364 days\ntwo leap years (1932 and 1936 | 6 | 1 term serving row 4 : 4 | kyösti kallio | 3 years, 293 days | 9 | * resigned due to poor health row 5 : 5 | risto ryti | 3 years, 229 days | 10 | * resigned due to agreement with nazi germany\n(after remainder row 6 : 6 | gustaf mannerheim | 1 year, 219 days | 11 | * resigned due to poor health and after not being prosecuted row 7 : 7 | j. k. paasikivi | 9 years, 356 days | 4 | 2 terms serving (remainder of mannerheim's and 1 row 8 : 8 | urho kekkonen | 25 years, 332 days | 1 | 3 whole terms serving (the 3rd exceptionally 10 years)\n row 9 : 9 | mauno koivisto | 12 years, 33 days | 2 | 2 terms serving row 10 : 10 | martti ahtisaari | 6 years, 0 days\ntwo leap years (1996 and 2000 | 5 | 1 term serving row 11 : 11 | tarja halonen | 12 years, 0 days | 3 | 2 terms serving row 12 : 12 | sauli niinistö | 2 years, 115 days | incumbent: first term serving | incumbent: first term serving
what is the number of presidents who resigned?
order in\nposition president of\nthe republic length of\nthe presidential\naction rank by\nlength\nof term(s) notes
1 K. J. Ståhlberg 5 years, 220 days 8 1 term serving
2 Lauri Kristian Relander 6 years, 0 days\none leap year (1928) 6 1 term serving
3 P. E. Svinhufvud 5 years, 364 days\ntwo leap years (1932 and 1936) 6 1 term serving
4 Kyösti Kallio 3 years, 293 days 9 * resigned due to poor health
5 Risto Ryti 3 years, 229 days 10 * resigned due to agreement with Nazi Germany\n(after remainder of Kallio's term and during 1 additional, exceptionally 2 years long term)
6 Gustaf Mannerheim 1 year, 219 days 11 * resigned due to poor health and after not being prosecuted in war responsibility trials
7 J. K. Paasikivi 9 years, 356 days 4 2 terms serving (remainder of Mannerheim's and 1 whole)
8 Urho Kekkonen 25 years, 332 days 1 3 whole terms serving (the 3rd exceptionally 10 years)\n* resigned during the 4th term due to poor health
9 Mauno Koivisto 12 years, 33 days 2 2 terms serving
10 Martti Ahtisaari 6 years, 0 days\ntwo leap years (1996 and 2000) 5 1 term serving
11 Tarja Halonen 12 years, 0 days 3 2 terms serving
12 Sauli Niinistö 2 years, 115 days incumbent: first term serving incumbent: first term serving
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