How many Major League Baseball seasons were lost due to strikes?

No entire seasons have been lost due to strikes, but Major League Baseball has had seven strikes or work stoppages:

1972: 13 days
1976: 17-day lockout in spring training
1980: 7 days during spring training
1981: 50 days
1985: 2 days
1990: 32-day lockout
1994-1995: 232 days, ’94 World Series canceled