The McClellan Summation Index is this formula on the $ADD chart.
Summation Index = 1000 + (10%Trend – 5%Trend) – ((10 x 10%Trend) + (20 x 5%Trend))
5%Trend = 39-day EMA of (Advancers-Decliners)
10%Trend = 19-day EMA of (Advancers-Decliners)
The symbol for the Advancers-Decliners is delayed but is available through IB as $ADD.
The formula is implemented with this DYO, and available on the Ensign web site using the Ensign 10 Package feature to download it.
A – Create the 39 period average.
B – Create the 19 period average.
C – Calculate the first half of the formula: 1000 + (10%Trend – 5%Trend)
D – Calculate the 2nd half of the formula: 10 * 10%Trend + 20 * 5%Trend
E – Subtract the two halves. Plot this result which is the Summation Index.