Two things just happened. One is not surprising. The other surprises me but probably won't surprise @Anonymous
Not surprising:
In EX report, 1 account went from zero to 23%, causing aggregate utilization to go from rounded 9% to rounded 10%.
FICO 8 -9
Just confirms that >9% is not great.
Surprising (to me at least):
You may ask what were the actual percentages which EX rounded to 9% and 10%.
8.93 % = 9%
9.35% = 10%
This surprises me because until today I had observed EX rounding the percentages up and down, contradicting @Anonymous 's theory that it always rounds up.
I'm going to have to watch it more closely now.
Update 2/2/19 9:43 PM
I just noticed that there are different rounded percentages on different pages.
On the tab headed "Credit Summary", 9.35% has been rounded up to 10%.
On the tab headed "Credit Report", it's rounded down to 9%.
Update 2/3/19
When one account dropped from 45% to below 1%, causing aggregate utilization to drop from 9.35% to 8.17%, the 9 points came back in FICO 8.
Experian rounded 8.17% down to 8%, on both the Credit Report and Credit Summary pages.
So on one page it was a drop from 10% to 8%; on another it was a drop from 9% to 8%.
I think that’s what everyone has been saying: the percentages do not “round”, they step.
9.35% is used as 10% in the scoring. That’s commonly presented, and the reason for the advice to stay below 8.9% to avoid that 10% threshold.
It is the specific reason some of us have been frustrated with your scoring updates, because those rounded displays are useless in confirming what the score is actually using. Actual percentages are needed. Not fluffy rounding. Now you know 
Looking back at prior posts, the following were rounded down, not up:
8.14% = 8%
12.25% = 12%
6.43% = 6%
9.16% = 9%
Where do the numbers on the left come from?
@NRB525 wrote:
Where do the numbers on the left come from?
EX's number for total revolving debt/EX's number for total revolving limits
SJ, when I have inconsistencies in my interpretation of what the MyFICO alerts are tellling me, it is usually some mistake or misunderstanding on my side. The algorithm and presentation of these data should be consistent.
@NRB525 wrote:
SJ, when I have inconsistencies in my interpretation of what the MyFICO alerts are tellling me, it is usually some mistake or misunderstanding on my side. The algorithm and presentation of these data should be consistent.
As I have repeatedly stated, my observations are based solely on daily changes in scores & data on experian.com, and have nothing to do with MyFICO.
@Anonymous wrote:
@SouthJamaica wrote:Update 2/2/19 9:43 PM
I just noticed that there are different rounded percentages on different pages.
On the tab headed "Credit Summary", 9.35% has been rounded up to 10%.
On the tab headed "Credit Report", it's rounded down to 9%.
I saw that last month on on my Experian CreditWorks Premium report as well: 0.47% actual aggregate (40/8500) rounded down to 0% (by EX display software, so it's most likely irrelevant), when FICO will be using 1%.
One of my cards had a statement closing today, and I decided to check my Experian CreditWorks Premium account. I didn't get an email or sms alert (yet), but the correct balance of $135 out of $2000 is there. (Previously $40, I paid that long before it was due, and put a fresh $135 on the card because I'm testing 7% util this month on both cards.)
So my score went down 3 points at EX from 699 to 696 and the only things that changed from last month are ageing of 1 mo, first 'paid as agreed' on a credit card account, individual card utilization from 2% to 7% (6.75% actual, or 135/2000), and aggregate utilization from 0.47% actual (FICO 1%) to 1.59% (135/8500 or FICO 2%).
My only other card will go from 0/6500 to 453.41/6500, or 6.98% (FICO 7%) in a few days (statement close Feb 5). That will move number of accounts with balances from 1 to 2, and I'm sure that's another point loss. Then aggregate util will move from 2% to 7% (6.92% actual, FICO 7%), and I guess I'll lose some more points!
What a great game this is. lol
I haven't found number of accounts with balances to be a big mover of my FICO 8 score, just the FICO 2 score.
BTW, in comparing the "Credit Summary" page and the "Credit Report" page, I can see that when I switch to an older report, the Credit Report page goes back to the older report's data, while the Credit Summary page does not, and is therefore useless from a historical perspective.