Help to produce a chart with large data set

Hi Everyone
I was wondering whether someone can help me with an advise on the best way to draw a chrt.

I have attacahed a very simple file to illustrate my problem.

I have a very large data set, over 165k of rows. the spreadsheet has information of sales per sales person for each month. When i draw a graph as its large it doesnt make any sense as its not clear because of the amount of x-axis label.

In the sample spreadsheet I have attached it does show a problem I have.Can someone please tell me what will it be the best way in the attached sheet to present a meaningful and readable graph to show the sales person sales for each region for each month. it can be any suitable chart. the chart in sheet 1 is the one i am interested in

Thanks in advane