How can I do a monthly time-series correlation across a 5 year period in excel

Hi, 

Is anyone able to help with the following..

I am trying to conduct an analysis on the correlation between participants and Duties in £Million on a monthly basis over the last 5 years. 

I am not sure if correlation is the correct term but I am looking to do a statistical analysis between how one effects the other.

I already have the data analysis tool kit add in, 

Please find attached the data I am referring to.

Thank you in advance 🙂