Waterfall chart

Show how a starting value evolves through a sequence of positive / negative contributions to a final value — revenue waterfall (revenue → costs → margin), budget decomposition, P&L bridges.

The demo decomposes the Apollo program's $25.4 B lifetime cost (1973 closeout, in 1973 dollars) by the four big spending buckets: the Saturn V rocket family, the Apollo CSM + Lunar Module spacecraft, ground operations + tracking, and the rest of the R&D portfolio. Saturn V alone — Wernher von Braun's moon rocket — was 36 % of the program total.

Source: Apollo program — Costs — Wikipedia

Public surface

use wisp_chart::finance::{Waterfall, WaterfallRow};

let w = Waterfall::new(vec![
    WaterfallRow::summary("Start",   100.0),
    WaterfallRow::contribution("Revenue",  80.0),
    WaterfallRow::contribution("COGS",    -30.0),
    WaterfallRow::contribution("Opex",    -25.0),
    WaterfallRow::contribution("Tax",     -10.0),
    WaterfallRow::summary("End",     115.0),
]);

Row kinds