The graph is fairly simple, and the trend analysis should be linear, so y = ax + b. So for the below graph i would expect something like y = 16x + 5 (approximately)

When I look at the details for the trend however, I see following results:

So according to these coefficients above, the formula would be y = 0.0000000006940 x -1607

Can you elaborate on how to read the coefficients?