Q:

Excel: How is this graph even possible?

I made a line graph using two sets of data:

However, the blue line is totally out of place somehow and I have no idea why. I feel like I've checked everything. What could be going wrong?

A:

Following on from @fiso's answer, are you sure you have a scatter plot and not a stacked plot of some kind?

A:

For some reason the blue line in the graph is like the sum of both numbers, the blue and the pink. 

