How to change peak height in Excel I have a normal distributed bell curve (created in excel). I want to change the data so that the peak of the curve is reduced and the edges of the curve are increased, without changing the overall area under the curve.
I am not sure about the technical terms to be used here, but I just want to shift the data to reduce the peak by 5% in the bell curve.
 A: [I find myself in a conundrum. I expect this doesn't answer your question, but to express all the ways your question is unclear would take several more comments than the two there now. As such I think it's best to give an answer that superficially seems to respond to your conditions, and explain some of the things you'll need to clarify if it isn't what you want.]
If you really have a normal density ("normally distributed bell curve") for some given population mean $\mu$ and population standard deviation $\sigma$, then you can reduce the height of the peak to 95% of what it was if you increase the standard deviation by a multiple of $1/(1-0.05)\approx 1.0526$ that is, increase $\sigma$ by $5.26\%$. Assuming "increase the edges" means "make the pdf in the tail thicker", this will also achieve that.
The area will still be 1.

So if I've correctly understood the question, that does satisfy the conditions. [If you want to do it to a sample, subtract the mean, multiply by 1.0526, then add the mean back -- you do that to avoid shifting the mean when you multiply]
However, that won't change the kurtosis. If you really do want to change the kurtosis (presumably, standardized fourth moment kurtosis), you probably want to hold the variance constant, but you'll also need to be more explicit about what kinds of transformation you're seeking.
