PROPORTIONATELY
proportionately, pro rata
(adverb) in proportion
proportionately, proportionally
(adverb) to a proportionate degree; “your salary will rise proportionately to your workload”
proportionately
(adverb) in proportion; “the height of this wall must be reduced proportionately to give the room pleasant dimensions”
Source: WordNet® 3.1
Etymology
Adverb
proportionately (comparative more proportionately, superlative most proportionately)
In a proportionate manner; with due proportion; proportionally.
Source: Wiktionary
Pro*por"tion*ate*ly (, adv.
Definition: In a proportionate manner; with due proportion; proportionally.
PROPORTIONATE
Pro*por"tion*ate, a. Etym: [L. proportionatus. See Proportion.]
Definition: Adjusted to something else according to a proportion;
proportional. Longfellow.
What is proportionate to his transgression. Locke.
Pro*por"tion*ate, v. t. [imp. & p. p. Proportionated; p. pr. & vb. n.
Proportionating.] Etym: [Cf. Proportion, v.]
Definition: To make proportional; to adjust according to a settled rate, or
to due comparative relation; to proportion; as, to proportionate
punishment to crimes.
Source: Webster’s Unabridged Dictionary 1913 Edition