The GPA tells you where a bank is heading. The SVI tells you how much to trust that forecast. It measures the volatility of the performance signal itself: how steadily the GPA's six component ratings move across quarters. Drivers that move together give a low SVI and an earned grade; a grade resting on one good quarter gives a high SVI and a fragile grade. In short: the GPA tells you where a bank is heading, and the SVI tells you how far to trust that forecast. The SVI runs from 0 to 100, where 0 is the most stable, and comes with a 1 to 9 confidence grade, where 9 is the most confident. Tested out of sample on banks it never saw, the forecast is tighter where the SVI is low:
Low SVI · about 0 to 33 · 88% within ±0.8
Middle SVI · about 33 to 67 · 82% within ±0.8
High SVI · about 67 to 100 · 74% within ±0.8
High GPA · Low SVI: EarnedDurable strength you can count on.
High GPA · High SVI: LuckyA good quarter on a fragile base; one surprise from a downgrade.
Low GPA · Low SVI: StructuralA real, well-understood weakness.
Low GPA · High SVI: In motionA turnaround candidate; the direction of travel decides buy versus sell.
Why it matters. A strong grade is common; a strong grade you can rely on is rare. When you build a peer group, watch your peers' SVI too: high-SVI banks' numbers are noisier than they look. (Per-bank SVI can be added to the chart and table next.)
