In/Out Activity does not affect numbers as expected (Activity and Rainfall this month)

[SirElismyer]

Taking money from a bucket and releasing back into the budget by way of a negative rainfall (i.e. -100 In/Out) causes the Activity amount to change. Adding that money back in does not alter the Activity again.
A similar issue happens to the "Rainfall this month" amount in the bucket menu (clicking the ellipses). The example indicates that it has rained 200 this month when in reality the same 100 was put in twice.

Bucket	Balance	In/Out	Activity	Rainfall this month
Groceries	0	-	0	0
		+100
Groceries	100	-	0	100
		-100
Groceries	0	-	-100	100
		+100
Groceries	100	-	-100	200

This leaves us with 100 in groceries as before but now it appears that 100 has been spent when in reality nothing has happened. It also appears that I've put 200 into this account when in reality I've only put same 100 in twice.

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I think what I imagined the Rainfall this month was supposed to be indicating was how much has been taken out and put in over the course of a single month that was not an Transaction based amount (ie a positive expense into Groceries as a refund etc would not be Rainfall/income as I understand it).
Activity, however, would show all the changes to the amount in a given account through the month. In/Out through the buckets menu and transactional changes (spending/receiving monies by way of the Transactions/Accounts menu)
So I think the bug is that the Activity is not taking in consideration monies that have been added through the In/Out box and the Rainfall this month is not taking into consideration monies that have been taken out through the In/Out box.

Edit: I got a little lost in the bug and had to unravel my brain. Its better now.

[SirElismyer]

The exact same issue exists on the "In" line. taking money out, putting it in and taking it out changes the number each time without any real change happening.

[iffy]

Related to #182

[SirElismyer]

Agreed. I think there are some other aspects here that aren't covered there if you're happy to leave this one open

[Limezy]

As I already wrote it on #182, I think all these tricky discussions are related to what arithmetic definition you would give to in and activity objects. IMHO, things would be more clear if the following equation was always true (which is not the case as per today).

Last month's last day's balance+In+Activity=Current balance

Again, this is only my own opinion and I also understand why @iffy would more use something like

Activity = SUM(ABS(all in or out transactions))

[iffy]

Included in v0.66.4 release (AUTOMATED COMMENT)