Real age of Joan Rivers in The Swimmer
In the movie The Swimmer, Joan Rivers was:
34 years old
That was the real age of the celebrity according to our calculation.
The calculation of the shown age took into account the first day of the year in which the movie The Swimmer was released:
January 1, 1968
And the day in which Joan Rivers was born:June 08, 1933
Since movies usually don't take more than one year to be released since the beginning of the filming process, Joan Rivers may have been one year younger or one year older than the shown age while some scenes of the movie were being filmed.