lemme point all to a bit of statistics comprehension: last world started at 800, ended at 200, this one started at 1200, ended at 300 (to be optimistics..) this means player retention WORSENED by 300 units over 1200, this means this world fared worse than the last, in proportion.
Actually this world lost 900 players over a potential of 1200, or 3/4 of the population has gone, last world lost 600 over 800, so basically the same, but in a smaller sample and with less updates, and also in a longer time...project this server in the last one conditions, and you'll see the results.