四半期
- Q1 (first quarter)：第１四半期
- Q2 (second quarter)：第２四半期
- Q3 (third quarter)：第３四半期
- Q4 (fourth quarter)：第４四半期
「Q1」＝「first quarter」＝「第１四半期」のこと。
上期・下期
- H1 (first half)：上期
- H2 (second half)：下期
A quarter is a three-month period on a company’s financial calendar that acts as a basis for periodic financial reports and the paying of dividends. A quarter refers to one-fourth of a year and is typically expressed as Q1 for the first quarter, Q2 for the second quarter, and so forth. For example, a quarter is often shown with its relevant year, as in Q1 2021 or Q121, which represents the first quarter of the year 2021.
https://www.investopedia.com/terms/q/quarter.asp
