Blended average
One number averaged across things that behave differently — the most common way reports flatter themselves.
Definition
A blended average pools heterogeneous segments into a single figure: paid and organic leads in one CPL, all channels in one conversion rate, every program in one cost per enrollment.
The blend isn't always wrong — totals have their place — but a blended number can't support a segment-level decision. Reallocating between channels based on a cross-channel average is using one number to answer a question it structurally cannot answer.
Why it matters
Blends hide your best and worst performers inside the same digit. The classic failure: organic volume blended into paid CPL, making every paid channel look cheaper as your unpaid channels improve.
How Pennant treats it
Pennant computes cost and conversion metrics segmented by channel, program, and campus, with paid-source denominators — totals exist, but decisions get segment-level numbers.