Price Elasticity

[Elmirahon]

Dear Professors and Economics Experts,

I am working on my master thesis and my project is on finding price elasticity of a product such as indigestion remedy.

I have three year long data and I see that I have strong correlation between sales and seasonality and also I have strong medium correlation with promotions. However,I find no correlation between the product sales against CPI and Weekly National Earnings.

Can you please advise me what other factors might also play a role in demand for over-the-counter medicines, please.

Your help will be much appreciated.

Thank you,

Elmira