What looks like a long encrypted is really a cipher puzzle with self-contained clues that take several stages to unravel.
The first step is ...
... to take the first letter in each line. (In comments, kamenf has hinted at acrostics.) This gives:
Remove digits first, then jump.
The next step ...
... is to strip all numerals from the code. But what does "jump" mean? The title has a hint: 11.1% is one ninth. Jumping to every ninth letter of the message gives:
Cut these letters, then Vigenere.
The alphabet is "the alphabet is".
The key is "the key is".
So the code ...
... was encrypted with a keyed Vigenère cipher. The key to the alphabet and the Vigenère key are helpfully provided. Decoding yields:
really, i gtwa
kru cvxbrJmnbgnqspb jj yld
jrtg fbMumat Ag kkc.
The beginning looks promising, but after that, it's just gibberish.
Okay, next attempt:
This is an "autokey" Vigenère cipher that uses the key only once and works with the plaintext after that. Decoding results in:
really, i give
you congrAtulations on all
your efForts So far.
you have done very well.
these PUzzles are
arguably not always easy eXercises but you have
deftly shown a great disPlay of your abilities to this
point. yet
if yoU wISh to wholly FulFil
all of the requiremenT expected out of
this puzzling JourneY, you must step back
To Find What or who you are trying to
Find. to begin, here is
the OBject of your Struggle, which
is to say the thing i ask for.
without determining this, there cannot be a way for
you to ultimately find
the answer you have come
to seek, and so you must
find the aim of this
challenge. so you are hereby tasked,
iF you darE, to
answer this: tell us why have
i made this cool
PUzzle
The code has ...
... capital letters in unusual places. They are:
AFSPUXPUISFFTJYTFWFOBSFEPU
I didn't know what to do with them, but Irishpanda has given me a leg up in the comments: Caesar-shift one back and we get:
Zero, two, three, six, seven are dot.
Now, take a step back:
The first step in our process was to remove the digits. Now we need them again. There's a number on each line:
8022 262 5973 012 0
7 7 2862 2 357
9357 6480 3 777 6286
64 339 602 264 739
371 4400 35 0156 10
We're told that 0, 2, 3, 6 and 7 are dot. Surely that must mean that 1, 4, 5, 8 and 9 are dash — we've got a Morse code! Converting the digits as told gives:
−··· · −·−· ·− ··− ··· · ·−−· ··− −−·· −−··
·−·· · ··· ·− ·−· · ··· ··− ·−−· · ·−· ··−· ··− −·
This decodes to the final answer:
Because puzzles are super fun!
Well, this one definitely is. :)