I used excel and created a scatterplot graph and used the equation which was -31.024x+1216.9 and used that to solve for 11 and 12 and got 875 on november and 844 on december is this correct?
Or you could work with moving averages: Plot 3 monthly moving averages... extend the trend line/curve and use your next predicted moving average to find the predicted monthly figure and so on.
I would use a two or three quarter moving average. I wouldn't use a regression line because there doesn;t seem to be an obvious linear relationship looking at that data.
can you please try and do it bear my internet does not load. So in conclusion the last two months predicted averages are 1145.333 for November and 1239 for December.