Answer from Hank Wrote:The "Exp" column is short for "Experience"

When this number is a decimal, like 1500.00 or 1650/9K ... this is the ELO for this member the "/9K" is 9000 matches for example.
The 1500.00 ... this is a new member, never played a match here yet.

The ELO value only shows in this tool when there is a "match type" to align it to. Since SimplyBG supports tracking on ELO based on types of matches being played.

So then this column "Exp" will show the ELO when the member has a "match-offer" active for the Openplay parlour. It's considered the players sort of standing offer.

But when the member does not have an active "match-offer" ... the "Exp" column will display the total matches played for this member.
This is a non-decimal value, like 1463

If you ever want to be reminded of what the column is showing, click on the "Exp" in the column header. It will show a small and brief reminder.
Your question is one that many probably have. Thanks for asking.