
That's 4.9 Penny Blossoms PER hour.
The Big Bang Theory Season 2, Episode 18

Eighteen parts PER million.
The Big Bang Theory Season 8, Episode 9

He was so busy figuring out
how many parts PER million of urine...
The Big Bang Theory Season 8, Episode 9

"Koo" from Koothrappali
and "PER" from CooPER.
The Big Bang Theory Season 9, Episode 12

And the policeman says, "Did you know
you were going 85 miles PER hour?"
The Big Bang Theory Season 10, Episode 21