上半期（kami hanki）： The first half year

The fiscal year in Japan starts in April and ends in March. Therefore today is the end of the first half year. We call this 6 months kami hanki(上半期), literally top half term. Usually the persons in charge of accounting are vey busy at the end of September and the end of March.
From October to March is called shimo hanki(下半期), literally bottom half term.
Kami (上:top) and shimo (下:bottom) are prefix to mean half of something. The kanji character of kami (上) and shimo (下) are also read as jo (上) and ka (下) or ge (下).
For example the first 10days of the month is called jo jun(上旬), and the last 10 days of the month is called ge jun(下旬). The top shelf is called jo dan(上段), and the bottom shelf is called ge dan(下段). Elegant is jo hin(上品), and dirty is ge hin(下品). Upper is jo ryu (上流), lower is ka ryu(下流). The upper half of the body is called jyo hanshin(上半身) and the lower half of the body is caled ka hanshin (下半身). The first book of the two volumes is called jo kan (上巻), and the second book of the two volumes is called ge kan (下巻). The Upper chamber is jo in (上院), the Lower chamber is ka in (下院).
If those two kanji characters are written as 上下, it is read as joge.