The way decay works in this game hugely bothers me...like HUGELY.
So in a bit of manic obsession I decided to "long hand" a visual representation of the amount of grief players can look forward to in their anticipation of getting Rank 5. Assuming my basic math holds up at 5 am in the morning after just waking up, and my understanding of how the PP decay is accepted in interpretation; it reads as the follows.
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[ E = Earned that week, R = Rolled over total value from previous week, w# = Week it happened ]
A very hardcore earning blitz
10,000 ( E w1 )
5,0000 ( R w1 ) + 5,000 ( E w2 ) = 10,000
5,0000 ( R w2 ) + 2,500 ( R w1 ) + 2,500 ( E w3 ) = 10,000
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5,0000 ( R w3 ) + 2,500 ( R w2 ) + 1,250 ( R w1 ) + 1,250 ( E w4 ) = 10,000
5,0000 ( R w4 ) + 2,500 ( R w3 ) + 1,250 ( R w2 ) + 1,250 ( E w5 ) = 10,000
/ 17,500 total merits earned to benefit from 1,250 a week. In 3 weeks. 100 million credits earned.
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[ Using the same format as the above ]
A less intensive Hardcore earning, now a consistent 3,000 merits a week instead.
Values are rounded up to the nearest once place, giving a mildly generous increase in returns.
3,000
1500 + 3000 = 4500
2250 + 750 + 3000 = 6000
3000 + 1125 + 375 + 3000 = 7500
3750 + 1500 + 563 + 3000 = 8813
4407 + 1875 + 750 + 3000 = 10,032
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/18,000 total earned after 6 weeks to reach 10k. 25 million credits earned.
5016 + 2204 + 938 + 1842 = 10,000
5000 + 2508 + 1102 + 1390= 10,000
5000 + 2500 + 1254 + 1246 = 10,000
/ 21,088 total earned after 8 weeks to benefit from 1,250 a week. 35 million credits earned.
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[ Using the same format as the above ]
A very 'casual' earning of 1,500 merits a week.
Values are rounded up to the nearest once place, giving a mildly generous increase in returns.
1,500
750 + 1500 = 2250
1125 + 375 + 1500 = 3000
1,500 + 563 + 188 + 1500 = 3751
1876 + 750 + 282 + 1500 = 4408
2204 + 938 + 375 + 1500 = 5017
2509 + 1102 + 469 + 1500 = 5580
2790 + 1255 + 551 + 1500 = 6096
3048 + 1395 + 628 + 1500 = 6571
3286 + 1524 + 698 + 1500 = 7008 / 10 weeks
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3504 + 1643 + 762 + 1500 = 7409
3705 + 1752 + 822 + 1500 = 7779
/18,000 total merits earned after 12 weeks and still only 3/4 the way to 10k . 55 million credits earned.
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3890 + 1853 + 876 + 1500 = 8119
4060 + 1945 + 927 + 1500 = 8432
4216 + 2030 + 973 + 1500 = 8719
4360 + 2108 + 1015 + 1500 = 8983
4492 + 2180 + 1054 + 1500 = 9226
4613 + 2246 + 1090 + 1500 = 9449
4725 + 2307 + 1123 + 1500 = 9655
4828 + 2362 + 1154 + 1500 = 9844 / 20 weeks
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4922 + 2414 + 1182 + 1500 = 10,018
/ 31,500 total merits earned after 21 weeks to reach 10k. 105 million credits earned.
5009 + 2461 + 1207 + 1500 = 10,117
5089 + 2505 + 1231 + 1175 = 10,000
5000 + 2544 + 1253 + 1203 = 10,000
or
5009 + 2461 + 1207 + 1383 = 10,000
5000 + 2505 + 1231 + 1264 = 10,000
5000 + 2500 + 1253 + 1247 = 10,000
Still requires an additional 2 weeks of higher earning to benefit from 1,250 a week. `34,200 merits
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TLDR;
What this shows is that 'weeks required' to reach 10k merits, depending on your income, is on a crazy huge curve; pretty much tripling each time you earn less and less per week.
Not only that, but the 'merits earned' during that time is outrageous; doubling the needed merits to be earned to reach the same spot when your income is only a measly 1500 a week.
The worse culprit, is the decay system itself, as seen after 10 weeks in the 1500 example. At 18,000 merits earned, having earned 500 more than you need in the first example, you are still only 3/4 the way to reaching 10k. And yet, that last 1/4 hurdle will require you to double your earned merits and double the weeks spent earning said merits.
You earn less credits as a byproduct as well, earning easily half as much or less for the same work.
In a philosophical and political expression, this is the epitome of "The Rich get Richer, and the Poor get Poorer".