The formula I am using is (Change from end 2017)/(End 2017 -1) expressed as a percentage.
It measures the players rate of progress towards the number 1 slot. It should work fine until we get a player who ends a season at number 1. I am not sure what Excel does when you ask it to divide by zero.
Returning to youngest pro breakthroughs, and whether it denotes a likelihood towards achieving a higher rank in the professional game - not really. The data is incomplete, which is a shame, some of the values may be off by a bit here and there becasue of missing weeks, or short weeks (where the Tennis Abstract data only runs to 300, or 600 of the ranked total players for some reason). But, the general idea is correct and interesting in itself. Here's what I have:
You can type in the red box to search for a name - here I've looked for all names containing "anna", and you can see the results. Click the cross in the box to reset the search and enter a different value.
You can hover over any individual dot to see the full details - either after searching, or just on the starting version.
This week we have had 5 players in MD action at full WTA level in non-Domestic events. I exclude Wimbledon for the purposes of this investigation, as it is not a WTA event.
This appears to be the highest such number since at least 1990.
Our previous best was in Week 35, 2012, when we had 4 such players: In Dallas, Annie K was DA, Hev was a WC, and Emily WS was a LL; in New Haven, Laura was DA
If you include domestic events, where our totals are routinely heavily bolstered by WC, then we have had as many as 7 players in WTA MD action in the 1990-2018 span
The high numbers, 6 or 7, only ever seem to happen in Edgbaston/Birmingham week - never at Nottingham, Manchester or Eastbourne.
The last time we had 7 was also in 2012, all in Birmingham: Bally, Annie, Laura & Hev were all DA; Sam Murray, Mel South & Tara were all WC
Two unranked players there in the top 15 which is also interesting.
Just to be clear, I am informed that this is not the top 15 players that win the highest % of their matches after taking the opening set. We have lots of players that have only won set 1 on 1 or 2 occasions, but have won all of those matches. Francesca would be 27th in the list from the top down including all players. This excerpt is just showing the more prominent players and those that have played a significant number of applicable matches.
Attention is drawn in the clarification to some notable achievements: Danielle Daley - 5 out of 5 when winning set 1 Emily Aruthnott - 9 out of 9 Emma Raducanu - an amazing 13 out of 13
66 Brits have won an opening set in 2018, and no player with more than one such match has a losing record after winning the opening set - as you'd imagine perhaps, but underscores the importance of that first set.
Or, "If I could figure out how to get the full 66 in one readable picture for review, I would, but I can't coz I'm lazy, so "
Re CH, maybe just written beside the name as additional info. I agree to my non expert eyes it would seem difficult to introduce it into the format as is without cluttering up what is very good as it is.