Equation to figure out amount left by month

[carliw1309]

I am trying to figure out an equation to help me figure out:
If I want to invest $22k a year, and so far I have invested $6k, I know how much I need to invest per month to get me to $22k BUT I want to have an equation that figures out PER MONTH what I need to invest once that amount invested has changed.
So for instance, I have 7 months left in the year, I need to invest $2285 each month to meet my goal. But if next month, I put in $3k, now my monthly goal is ($22k-$9k)/6 months = $2166
Sorry, it's the only way I can explain it because I don't know the terminology.
But if it's possible, I would like it to auto populate the months remaining. I don't know if this is possible.
Thanks!!!!

 

[Snakehips]

@carliw1309 Welcome.
This probably won't match your layout but may give you an idea?
Click the Copy icon at the top left of the display below and then you can then paste it into a blank sheet to test it.

Book1.xlsx
	A	B	C	D	E	F	G	H	I	J	K	L	M	N	O	P
1
2
3	Year Start	1/1/23		Month	January	February	March	April	May	June	July	August	September	October	November	December
4	Annual Target	22000		Monthly Target	-	-	-	-	-	-	2166.67	2166.67	2166.67	2166.67	2166.67	2166.67
5	Invested To Date	9000		Invested	2000	0	1000	1500	1500	3000
6
7
8								*Enter 0 if no investment made for a given month
9
Sheet8

Cell Formulas
Range	Formula
E3:P3	E3	=$B3+COLUMNS($E1:E1)*28
E4:P4	E4	=IF(AND(ISNUMBER(E5),E5>-1),"-",($B4-$B5)/COUNTIF($E5:$P5,""))
B5	B5	=SUM(E5:P5)