Inventory includes all items required to make, store or sell your stock.
[1] Stock-taking may be performed as an intensive annual, end of fiscal year, procedure or may be done continuously by means of a cycle count.
[2] An annual end of fiscal year stock-taking is typically undertaken for use in a company's financial statements.
However, "periodic" may also refer to half yearly, seasonal, quarterly, monthly, bi-monthly or daily.
However, such stock-taking tasks are often laborious and often lead to significant warehouse operational downtime, ranging from days to weeks.