Index Top Holdings Advance Decline

This indicator measures advance vs decline for the top 10 holdings of either SPX or NDX, or both together.

There's overlap within the top holdings for the two major indexes so by default SPX is only shown.

Adjustments to top holdings can be done at any time should they be updated before I adjust the script, also the threshold of when advancement or decline should be considered strong is defaulted to six holdings but adjust to preference.

The idea came out of a discord conversation and the results are compelling, and it's usage should be similar to the market internal ADD, which measures amount of stocks in broad market over or under previous session range.

If this indicator receives enough traction I'll look into creating a volume (VOLD), price (TICK) and perhaps some other versions - perhaps even one that combines it all together like my MIT indicator for market internals.