Derog deleted based on GW letter, FICO dropped a point

[Anonymous]

I recently convinced an old credit card with a Date of Originial Delinquency of April 2014 to delete based on a GW letter.  It was reporting as a charge off with zero balance (paid shortly after the CO back then).   According to my MyFico updates it shows as deleted on TU but that score actually went down 1 point.  It's gone from Experian as well because I pulled that report from Annual Credit Report but I have yet to recieve the MyFico update.  Still waiting on EQ.  The alerts actually say that a Bankcard was removed, decrease in amounts past due, and a delinquent/past due account was removed as the reasons for the score change.

As it relates to TU, is it common for the score to actually drop a point???  I was expecting a little bump.  Is it possible since it was closed and paid almost 4 years ago it really wasn't impacting my score?

Eq: 650 (from 634 on 10/1/17)

Tu: 680 (from 648 on 10/1/17)

Ex: 667 (from 636 on 10/1/17)

[Anonymous]

1. Do you have other derogs?
2. If yes, was it your oldest derog?
3. If yes, then yes, score drop.

[Anonymous]

Hi and thanks for the response. Yes. There are other derogs. They are:

Negatives

Two other Credit Cards: CO around the same time as the one mentioned above. Like the ones above, they were also PIF shortly after the CO.
Old Car Loan: Two 30's April 2016.
Student Loans: A few 60's at the end of '13

I’ve had no issue getting new credit recently. AMEX 4K, C1QS 3k, and WFCashWise 4K.

Curious, what would be the reason for the dip?