Today I noticed that the results of one of our polls is incorrect:
This poll uses 5 radio button and people can only select 1.
(see attached picture)
97 people voted
A.16 votes (should be 16%), but shows 16%
B.20 votes (should be 21%), but shows 20%
C.16 votes (should be 16%), but shows 16%
D.25 votes (should be 26%), but shows 25%
E.20 votes (should be 21%), but shows 20%

What's causing this ?