VectorPaint cumulative waterfalls: connect floating changes to successive totals

English translation of the Chinese original, translated on 2026-11-04. Original publication dates, attribution, code and version notes are retained.

A cumulative waterfall distinguishes running totals from individual changes. Use fictional values of 10, +3, −4 and +2 to build a start, floating change bars and an ending total. Calculate in a source list; VectorPaint supplies the drawing, not automatic arithmetic. These are exercise units rather than financial or business records.

Calculate before-and-after totals first

List a start of 10, then 13 after adding 3, 9 after subtracting 4, and 11 after adding 2. Each row needs the change, total before and total after, not just three signed numbers. Verify 10+3−4+2=11 manually before drawing. On a 1200 by 800 pixel canvas, reserve five columns for the start, three changes and end. Use invented relative units and label the title as a fictional exercise. If future values use different measurement bases, establish that they can be added first; putting every number into a cumulative layout and explaining with colour cannot make incompatible quantities additive.

Use one y scale and a stable column layout

Use a y axis from 0 to 14 with equally spaced checkable ticks, locating heights such as 3, 9, 11 and 13 through the same unit interval. Keep all five columns equally wide and spaced; start and end do not gain width because their names seem more important. Draw axes and temporary positional references first and leave clearance above 13. Hand-drawn references are artwork you may retain as needed; inspect actual export for native grids and guides. All bar heights use the same y scale rather than independent scaling to similar-looking sizes. Keep column names and values in separate layers to avoid shifting labels while aligning graphics.

Draw complete start and end totals from zero

Draw the start rectangle from 0 to 10 and end from 0 to 11, initially using one total colour. They represent complete quantities, not changes of +10 or +11; label that role. Remove unnecessary strokes to inspect actual heights, since thick outlines can appear to cross ticks. Compare both bars with the list and confirm the end is slightly higher, without skipping the intervening changes. Keep start and end in independent groups. Any later change requires recalculating the end instead of moving middle bars while preserving an obsolete final total.

Anchor each floating change at the prior total

Draw +3 from 10 to 13, −4 between 9 and 13 with its downward direction labelled, and +2 from 9 to 11. A rectangle itself only has upper and lower edges; signs, labels and connections express the change direction. Starting every change at zero would express a different chart. Check before-and-after totals for each bar, especially that the −4 bar’s lower edge is 9 rather than −4. Colour may distinguish increases from decreases, but retain words and signs for monochrome reading. Visible bar height equals the absolute change, not the total at its upper edge.

Use connectors to show the running level

From each post-change level, draw a short horizontal connector toward the next column, lighter than the bars and ending clearly at the appropriate starting level. Connect start 10 to the +3 lower edge, 13 to the −4 upper edge, 9 to the +2 lower edge and 11 to the end’s upper edge. Arbitrary diagonals between rectangle centres obscure accumulation. Explain that connectors indicate continuity rather than another data series. Hide text and follow the path, then restore labels and calculate to verify agreement. Moving a bar requires checking both adjacent connectors; ordinary paths do not automatically follow numerical changes.

Test maintainability with one changed value

In a copy, replace −4 with −2. Recalculate the intermediate total as 11 and final total as 13 before adjusting the descending bar, later +2 bar and end. The earlier +3 remains unchanged. Editing only the signed label leaves incorrect later heights. Keep the same axis and verify the new maximum still fits. Restore the original or save a new list and drawing with the values identified in their names. This test shows that cumulative edits affect later elements rather than independent cards; understanding the dependency also supports adding future steps consistently.

Check arithmetic and geometry after export

Save the source and inspect the export by reading 10+3−4+2=11, then identifying every upper and lower bar height. Check small signs: the minus must not disappear as a decorative dash. Retain title, units and fictional-data scope rather than cropping floating bars out of context. At actual size, connectors should not overpower bars and text should not cover boundaries. Include data revision and size in the filename and reopen the delivery file to exclude modified-value tests. Real use still needs source and scope verification: expressing the calculation does not authenticate the input data.

Locate the first cumulative mismatch

If the end is not 11, check signs and arithmetic in the list, then find the first divergent cumulative level instead of forcing the final bar to the expected height. If a decrease looks upward, inspect its sign, colour and which end receives the connector. A correct bar height can still sit at the wrong level, so compare both change amount and starting total. For overlapping exported lines, check duplicate copies and excessive strokes. Recalculate all downstream totals after repairs and repeat the text-hidden continuity check. Retain the exercise only when both numbers and geometry can be explained.