Raw difference (Current - Previous).
Relative change expressed as a fraction ((Current - Previous) / Previous,
e.g., 0.12 for +12%), or null when Previous === 0.
Current period value (first numeric field of the first row).
Comparison / previous period value (second numeric field of the first row).
Frozen value for a
'Delta'data binding, computed from the first two numeric fields of the first row.