Top: cumulative ZEC balance in the Orchard shielded pool. Bottom: daily inflow and outflow lines. Orchard activated with Network Upgrade 5 (NU5) at block 1,687,104 and uses the Halo 2 proving system. It is the recommended pool for new shielded activity.
The upper panel is how much ZEC sits in the Orchard pool; the lower is how much moved in and out each day. A balance is a stock and a flow is a rate. Reading one as the other is the mistake this chart most invites. A falling balance with healthy flow in both directions is turnover; a falling balance with no flow is abandonment. They look the same on the top panel alone.
Both sides are exact, not estimated. Value entering or leaving a shielded pool crosses the transparent turnstile and is counted by consensus, which is why these numbers can be stated precisely while nothing about the holders can be. What stays hidden is everything inside: who, how much each, and moving to whom.
Orchard is where new shielded activity goes -- NU5, block 1,687,104, Halo 2 -- so its inflow carries both fresh shielding and migration out of Sapling, and the chart cannot tell them apart. It is also the pool the turnstile audit is about.
For all pools on one axis see shielded pool balances, or net flows compared for the same question asked of direction alone.