"Biff" wrote:
30,000 helper cells!

Ah, but that doesn't mean it doesn't/won't work <g
It's just a suggestion for the OP to try out, of course ..
The number may be sizeable, but the formulas are simple
The longer extract formulas on each tech's sheet
are kept to a sufficiently modest ~100 cells per sheet (5K total)
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Rgds
Max
xl 97
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xdemechanik
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