Grammar
-(으)ㄹ 것으로 추산하다
Meaning
Expert-(eu)l geoseuro chusanhada
추산하다 (推算) is to arrive at a figure by calculating from partial data rather than by counting it. A future clause is packaged as a noun with -(으)ㄹ 것, handed to the verb with 으로, and the sentence then says that a named body worked the number out: 정부는 세수가 늘어날 것으로 추산했습니다 means the government calculated that tax revenue would rise. Two things follow from the choice of this verb. It is active, so the estimator stays in the sentence as its subject and can be held to the number; and 추산 itself says the number is computed, not counted, so the figure is explicitly an estimate.
Form
Verb stem + -(으)ㄹ 것으로 추산하다. Use -ㄹ 것으로 after a vowel-final stem (늘어나다 → 늘어날 것으로), -을 것으로 after a consonant-final stem (넘다 → 넘을 것으로), and drop a stem-final ㄹ (늘다 → 늘 것으로). The body doing the estimating is the sentence subject, normally an institution or research team marked with 은/는 or 이/가, and news almost always writes the verb in the past — 추산했다, 추산했습니다 — because an estimate is issued at a particular moment. The amount sits inside the embedded clause, usually with 을/를 넘다, N에 이르다, or a bare number: 3조 4000억원 이상 늘어날 것으로 추산했습니다.
Examples
연구진은 참가자가 만 명을 넘을 것으로 추산했습니다.
The research team estimated that the number of participants would exceed ten thousand.
한 연구 기관은 이 법안으로 세수가 2조 원 줄 것으로 추산했습니다.
A research body estimated that the bill would reduce tax revenue by 2 trillion won.
시는 축제 기간 방문객이 50만 명에 이를 것으로 추산했습니다.
The city estimated that visitors over the festival period would reach 500,000.
Common mistakes & nuance
추산하다 comes with a figure. It is the verb for how big something is when nobody can count it exactly — forgone tax revenue, crowd size, unregistered residents — so a sentence with no number in it wants -(으)ㄹ 것으로 전망하다 instead. The other thing to watch is the active voice. This frame and 전망하다 keep the estimator visible; the passive members of the same family (기대되다, 나타나다, 확인되다) delete whoever is behind the claim, and a reader who does not notice the difference cannot tell whose number they are reading. Note too that the ending before 것 is the prospective modifier -(으)ㄹ, never the object particle 를: 넘을 것으로, not 넘를 것으로.
Similar grammar
- -(으)ㄹ 것으로 전망하다
Both are active, so both name whoever made the call. The difference is what is being produced: 추산하다 produces a number worked out from data, while 전망하다 produces an outlook over a period and needs no figure at all.
- -(으)ㄹ 것으로 예상되다
예상되다 is passive: nobody is named as the one expecting it, and 예상 is a plain expectation rather than a calculation. 추산하다 does the opposite on both counts — it names the estimator and says the figure was computed.