NTE wrote:
: No. The data is as shown above, no empty cells. Thank you.

I think it is clear that the problem is caused by your error bars.
You say you do not get lower bars, this is because the lower
confidence interval covers zero so they are all negative.

Error would be computed as Y+/- = X +/- error.
Since X is very small it is easy to see how Y could be negative.
Probably the only error bars you could plot would be % choice on
the menu. This would keep the numbers positive since
the computation would be Y+/- = X * (1+/%). (Assuming you
keep % less than 100%)

The other choices are all absolute numbers which could
easily result in negative numbers for the lower limit.

Pieter Vandenberg