This function calculates several summary statistics for time series data. The function calculates the following metrics for all key combinations:
start
: Start date (or date-time)end
: End date (or date-time)n_obs
: Number of observations per time seriesn_missing
: Number of missing values (NAs)pct_missing
: Percentage rate of missing valuesn_zeros
: Number of zero valuespct_zeros
: Percentage rate of zero values