How do I know my Forecast formula is correct

[syed82]

I have 2 years of data and trying to project forecast of the future chart should be. However, it seem chart is not as expected or probably i plot the wrong info

appreciate your expertise on this area

i also attached file for easy reference

[Glenn Kennedy]

I can not see through your eyes.

What do you mean by "it seem chart is not as expected". What did you expect to see?

[syed82]

Well.. as i see fy 2017 & 2018.. graph show high and low.. however, when i forecast my graph based on 2 years and seem figure balance.. there is no very high or low. So i thought maybe i’m wrongly plot the formula range. Appreciate if you could check sample attached..

[davsth]

The forecast function forecasts a value based on known Xs and Ys

You appear to be using the previous year as your y and the year before as your x. You have not explained what your data is but this seems a strange approach
what do row 1 mean? are they dates but you only look at the start of each month? Or are they weeks. usually you forecast against time.

In words can you explain the logic behind how you wish to forecast. I share Glenn's comment, we can not see through your eyes.

[syed82]

That forecast is on weekly projection for the past 2 years and data for 2019 only up to april 1st.
The weekly formula read as “1st - 8th : 1st week”, “9th - 16th : 2nd week”, “17th - 24th : 3rd week” and 25 - 31st : 4 week”

That why i’m confuse of range to plot.. or is it this forecast formula can’t text ? Or could you project forecast based on fy2019 as your vision. I’m not really understand this formula yet