Here's how we use QTR, FY, and TTM figures in our Fundamentals data and calculations.
For Fundamentals:
If we don’t specify QTR or FY, the API will return TTM (trailing twelve months) by default. The trailing dividend yield is the last twelve months dividends which we source from the exchange, for example, so we receive that data much earlier than the dividendyield tag calculation
TTM cannot be used in balance sheet as balance sheet is already a point in time statement. It only works for income statement and cash flow.
When specifying QTR as the "type" in a call, it's using the data from a given fiscal quarterly period - i.e. the latest equity figure, net income, etc. from the last fiscal quarter. TTM would use the trailing 12-month net income data, for example, and any other income statement or cash flow statement data used in the calculation, as would any of our other TTM calculations.
For calculations:
It depends on what type of metrics and how often they are reported. If the child variables are available quarterly and annually, both will be available to query.
For instance: pricetoearnings is derived from close_price/(netincome/weightedavedilutedsharesos)
close_price comes from the security close price received daily, and net income and weighted average diluted shares outstanding come from the income statement, received quarterly and annually.