Use this to visualize spending trends, identify fiscal-year-end spikes,
or compare spending patterns across years.

Note: The API returns fiscal_year as a STRING. Cast to int for numeric
comparisons. quarter and month are FISCAL periods (month 1 = October,
quarter 1 = October-December). Buckets are clipped to the window, so a
calendar-2025 window returns a partial fiscal_year '2025' (January-
September only) and a partial '2026' (October-December); neither is
that whole fiscal year.

DoD contract actions are published 90 days late, so when the window
reaches into the last 90 days and DoD is in scope the answer carries a
data_note: those months are understated, so don't read them as a drop.

awarding_agency must be a TOPTIER agency name ('Department of Defense').
Military departments are subtiers: pass
awarding_subagency='Department of the Navy'. A non-toptier name in
awarding_agency (or a subagency that does not belong to the given
toptier) silently returns all-zero aggregates.

At least one filter is required (the API rejects empty filter sets with HTTP 400).
Typical usage: pass time_period_start + time_period_end.

date_type controls the transaction date window. Omitted (the default)
or 'action_date', it selects transaction actions inside the window.
'date_signed' selects the associated award's first signing date;
'last_modified_date' selects transaction update dates. 'new_awards_only'
retains in-window actions associated with awards first signed in the
window. These are transaction obligation totals, not new-award counts:
use new_awards_over_time for counts. Award search/count tools use a
different default interval-overlap rule.
date_type needs time_period_start and/or time_period_end.

program_numbers filters assistance awards by assistance listing (CFDA)
number, e.g. ['93.778'] for Medicaid; use it with award_type='grants',
'loans', 'direct_payments', or 'other'. autocomplete_cfda() finds numbers
by program name.