Hōryaku calendar

The Hōryaku calendar (宝暦暦) was a Japanese lunisolar calendar (genka reki). It was also known as Hōryaku Kōjutsu Gen-reki (宝暦甲戌元暦). It was published in 1755.

History
The Hōryaku Kōjutsu Genreki system was the work of Abe Yasukuni, Shibukawa Kōkyō, and Nishiyama Seikyū. Errors in the calendar were corrected in 1798 and in 1844. In 1872, the Western calendar was adopted.