Normal Distribution line

[oz_orlando]

I have a frequency chart, can show the graph in column charts, but
want to map a normal distribution over the top.
so far I generated a normal distribution through the normdist function
but I couldn't get an accurate stdev, and the curve was always centre
across the 15 x values instead of centring on the mean. Any ideas on
good way to map a normal distribution, or possible ways of centerin
what i have created over the mean rather than the 15 x values i have.
thank