This year will be our 20th statistical survey since we started doing it in the year 2000.
It's been 20 years since we started doing this statistical survey.
ーThis year will be our 20th statistical survey since we started doing it in the year 2000.
「２０００年に始めて以来、今年で２０回目の統計調査になります。」
「統計調査」は statistical survey
20th statistical survey で「２０回目の統計調査」
ーIt's been 20 years since we started doing this statistical survey.
「我々が統計調査を始めてから２０年になります。」
It's been 20 years since ... で「…以来２０年が経った」
このように現在完了形を使っても表現できます。
ご参考まで！
This survey, which began in 2000, is being conducted for the 20th time this year.
This survey, which began in 2000, is being conducted for the 20th time this year.
This year marks the 20th edition of the survey that started in 2000.
This survey started in 2000, and this year is its 20th anniversary.
「統計調査は、今年で20回目を迎えます」は英語では、
"marks the 20th edition"
「第20回を迎える」
や、
"for the 20th time"
「20回目として」
などを使うと自然です。
カナダ 
アメリカ合衆国 
