Suggest New Balance Based on Target +/- Previous Balance

Hi guys, not able to crack this one up... would you be able to suggest please?

Attaching the screenshots & file below. Basically all I'm trying to achieve here is:

1. I have yearly income target
2. Yearly suggests monthly income target
3. Actual income is generated each month
4. Suggest new monthly income target, based on actual, so that yearly income target is still to be achieved

Thanking in advance!

https://www.excelforum.com/attachmen...1&d=1521038301 [EXCEL]

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