Chanderpaul occupy three adjacent spots (5th, 6th and 7th) on the overall Test run-scorers list, which means that they are also the 1st, 2nd and 3rd most prolific left-handed batsmen in Test history - Allan Border, Alastair Cook, Graeme Smith, Matthew Hayden, David Gower, Garry Sobers and Justin Langer make up the rest of the top ten. Since Langer is 30th overall on the list, you can see that exactly one-third of the top 30 batsmen are left-handed, which gives you an insight into their prevalence in comparison to the prevalence of left-handedness in the population at large (about 10%). There is a catch here, though, which is that not all players who bat left-handed are left-handed in the traditional sense, i.e. doing the "normal" stuff like writing with their left hand. Gower and Lara, for instance, were left-handed batsman and right-handed writers (and occasional bowlers); conversely, Tendulkar batted and bowled right-handed and wrote with his left hand.
Both retirements also necessitate some revision of my obscure hierarchy of batting averages: Sangakkara ends Jacques Kallis' 18-month tenure on the overall list by replacing him. It's worth re-iterating the point of these lists: for each person appearing on it, no-one who has come later has finished with a higher average.
As you can see, Sangakkara wasn't that far from removing Garry Sobers from the list - before his last two matches against India he was averaging 58.04, and only needed to score 133 runs in his last match (rather than the 50 he actually did score) to finish with an average in excess of Sobers'. The 325 runs he would have needed to score to displace Ken Barrington would have been a tall order, and the 9240 runs he would have needed to score to displace Don Bradman definitely would have been.. Nonetheless he collapses the Sri Lankan list to a single entry, just as Kallis and Sachin Tendulkar did for their respective countries on their retirements. I should add, just for completeness, that Sangakkara's old mucker Mahela Jayawardene would have been occupying the Sri Lankan list on his own since his retirement in 2014 if I'd been scrupulous about keeping things up-to-date.
Chanderpaul still talks up his chances of a return to Test cricket, but I think we're pretty safe in assuming that that won't happen, just as we are for Kevin Pietersen of England. I therefore think it's safe to include them on their respective countries' lists. Chanderpaul displaces his old team-mate Ramnaresh Sarwan for West Indies, and Pietersen displaces everyone post-Boycott for England. Michael Clarke's retirement at the end of the recent Ashes series slots him in at the end of the Australian list.