NEP drop spading

ALL with perfectly fair coin. Talking spade used between changes.

Monsters have two "commons" and two "uncommons".
Most(?) commons start at 50%+, then go to 40%, then 20%, then 10%, and then finally stop diminishing at 5%.
The diminish only occurs upon SUCCESSFUL drops.
This makes me think they start at 80% (to support halve rate)
An exception is biker, whose common #2 appears to go to 45%, for some reason.
His drops might start at 90, and go to 45, 22.5 etc. I'd have to spade this next time.
It's probably worth spading each particular monster carefully. This data suggests most if not all the monsters except biker use 80->40->20->10->5.

All uncommons appear to start at 15% base, then go to 5, and then finally stop diminishing at 1%.
The diminish only occurs upon SUCCESSFUL drops.
You can have commons' drop rate be lower than uncommons' droprate: https://gyazo.com/ec5e4043e6f487d66f36563c53aba5d3

Number written in capitals above encounters were the order I fought the monsters. Number to the right of the encounter name is +item% and encounter number for that monster respectively.
YES means an item dropped. NO means an item didn't drop. (#number) is how many have dropped so far (inclusive).


ONE
party girl @205% #1
runproof mascara YES (#1)
very small red dress YES (#1)
noticeable pumps NO
surprisingly capacious handbag NO

SEVEN
party girl @5% #2
runproof mascara NO (#1)
very small red dress NO (#1)
noticeable pumps NO
surprisingly capacious handbag NO

party girl @25% #3
runproof mascara YES (#2)
very small red dress YES (#2)
noticeable pumps NO
surprisingly capacious handbag NO

TWO
jock @85% #1
unremarkable duffel bag YES (#1)
Purple Beast energy drink YES (#1)
cosmetic football NO
shoe ad T-shirt NO

EIGHT
jock @8% #2
unremarkable duffel bag NO (#1)
Purple Beast energy drink NO (#1)
cosmetic football NO
shoe ad T-shirt NO

THIRTEEN
jock @12% #3 CONFIRMED: common 2 not 45% base
unremarkable duffel bag NO (#1)
Purple Beast energy drink NO (#1)
cosmetic football NO
shoe ad T-shirt NO

jock @900% #4
unremarkable duffel bag YES (#2)
Purple Beast energy drink YES (#2)
cosmetic football YES (#1)
shoe ad T-shirt YES (#1)

THREE
burnout @10% #1
van key YES (#1)
jam band bootleg YES (#1)
denim jacket NO
ratty knitted cap NO

FIVE
burnout @0% #2
van key NO (#1)
jam band bootleg NO (#1)
denim jacket NO
ratty knitted cap NO

NINE
burnout @9% #3
van key NO (#1)
jam band bootleg NO (#1)
denim jacket NO
ratty knitted cap NO

ELEVEN
burnout @10% #4
van key NO (#1)
jam band bootleg NO (#1)
denim jacket NO
ratty knitted cap NO

burnout @12% #5 CONFIRMED: common 2 not 45% base
van key NO (#1)
jam band bootleg NO (#1)
denim jacket NO
ratty knitted cap NO

burnout @25% #6 common 2 40% base?
van key YES (#2)
jam band bootleg YES (#2)
denim jacket NO
ratty knitted cap NO

burnout @25% #7
van key NO (#2)
jam band bootleg NO (#2)
denim jacket NO
ratty knitted cap NO

burnout @43% #8
van key NO (#2)
jam band bootleg NO (#2)
denim jacket NO
ratty knitted cap NO

burnout @67% #9
van key NO (#2)
jam band bootleg NO (#2)
denim jacket NO
ratty knitted cap NO

burnout @100% #10
van key NO (#2)
jam band bootleg NO (#2)
denim jacket NO
ratty knitted cap NO

burnout @150% #11 CONFIRMED: common 3 is 20% base
van key YES (#3)
jam band bootleg YES (#3)
denim jacket NO
ratty knitted cap NO

burnout @150% #12
van key NO (#3)
jam band bootleg NO (#3)
denim jacket NO
ratty knitted cap NO

burnout @234% #13 CONFIRMED: uncommon 1 is 15% base
van key NO (#3) !!
jam band bootleg NO (#3) !!
denim jacket YES (#1)
ratty knitted cap YES (#1)

burnout @234% #14
van key NO (#3)
jam band bootleg NO (#3)
denim jacket NO (#1)
ratty knitted cap NO (#1)

burnout @400% #15 CONFIRMED: common 4 is 10% base
van key YES (#4)
jam band bootleg YES (#4)
denim jacket NO (#1)
ratty knitted cap NO (#1)

burnout @400% #16
van key NO (#4)
jam band bootleg NO (#4)
denim jacket NO (#1)
ratty knitted cap NO (#1)

burnout @900% #17 CONFIRMED: common 5 is 5% base; CONFIRMED: uncommon 2 is 5% base
van key YES (#5)
jam band bootleg YES (#5)
denim jacket YES (#2)
ratty knitted cap YES (#2)

burnout @900% #18 CONFIRMED: common 5 does not diminish after 5% base
van key YES (#6)
jam band bootleg YES (#6)
denim jacket NO (#2)
ratty knitted cap NO (#2)

burnout @5392% #19 CONFIRMED: uncommon 3 is 1% base
van key YES (#7)
jam band bootleg YES (#7)
denim jacket YES (#3)
ratty knitted cap YES (#3)

burnout @5392% #20 CONFIRMED: uncommon 3 does not diminish after 1% base
van key YES (#8)
jam band bootleg YES (#8)
denim jacket YES (#4)
ratty knitted cap YES (#4)

FOUR
a "plain" girl @-90% #1
electronics kit NO
PB&J with the crusts cut off NO
dorky glasses NO
ponytail clip NO

TEN
a "plain" girl @10% #2
electronics kit YES (#1)
PB&J with the crusts cut off YES (#1)
dorky glasses NO
ponytail clip NO

a "plain" girl @150% #3
electronics kit YES (#2)
PB&J with the crusts cut off YES (#2)
dorky glasses NO
ponytail clip NO

a "plain" girl @400% #4
electronics kit YES (#3)
PB&J with the crusts cut off YES (#3)
dorky glasses YES (#1)
ponytail clip YES (#1)

a "plain" girl @400% #5
electronics kit YES (#4)
PB&J with the crusts cut off YES (#4)
dorky glasses NO (#1)
ponytail clip NO (#1)

a "plain" girl @400% #6
electronics kit NO (#4)
PB&J with the crusts cut off NO (#4)
dorky glasses NO (#1)
ponytail clip NO (#1)

SIX
biker @0% #1 CONFIRMED: common 1 is more than 50% base
gas can YES (#1)
Middle of the Road™ brand whiskey YES (#1)
neverending wallet chain NO
pentagram bandana NO

TWELVE
biker @12% #2 common 2 is 45% base? this seems wrong but double checked and I definitely had 12%
gas can YES (#2)
Middle of the Road™ brand whiskey YES (#2)
neverending wallet chain NO
pentagram bandana NO

biker @43% #3
gas can NO (#2)
Middle of the Road™ brand whiskey NO (#2)
neverending wallet chain NO
pentagram bandana NO

biker @400% #4
gas can YES (#3)
Middle of the Road™ brand whiskey YES (#3)
neverending wallet chain YES (#1)
pentagram bandana YES (#1)

biker @400% #5
gas can YES (#4)
Middle of the Road™ brand whiskey YES (#4)
neverending wallet chain NO (#1)
pentagram bandana NO (#1)

biker @900% #6
gas can YES (#5)
Middle of the Road™ brand whiskey YES (#5)
neverending wallet chain YES (#2)
pentagram bandana YES (#2)

biker @5392% #7
gas can YES (#6)
Middle of the Road™ brand whiskey YES (#6)
neverending wallet chain YES (#3)
pentagram bandana YES (#3)

biker @5392% #8
gas can YES (#7)
Middle of the Road™ brand whiskey YES (#7)
neverending wallet chain YES (#4)
pentagram bandana YES (#4)