Per Centum Access

If a whole is divided into 100 parts, a "percentage" indicates how many of those parts make up the subset being discussed.

"Percent" (one word) is standard American English, while "per cent" (two words) is more common in British English. How to Pronounce Percent - Deep English per centum

The core, simple formula for a percentage is If a whole is divided into 100 parts,

Percentages over 100% (e.g., 200%) signify a whole plus an additional amount (2 times the original amount). Related Technical Terms Per Mille (‰): Parts per thousand (1 in 1,000). per centum