The real author:

Umnyashkin Victor

The full investigation was conducted by Konstantin Kopyrkin. 

The formula for the calculation:

Anchored Momentum = 100 * (EMA[Price, EmaPeriod]  /  SMA[Price, SmaPeriod]  - 1

Indicator input parameters:

//+-----------------------------------+
//| INDICATOR INPUT PARAMETERS        |
//+-----------------------------------+
input uint MomPeriod=8; //the period of SMA 
input uint SmoothPeriod=6; //the period of EMA
input ENUM_APPLIED_PRICE IPC=PRICE_CLOSE;//price constant on which the indicator calculation is performed
input double UpLevel=+0.025; //upper breakthrough level
input double DnLevel=-0.025; //lower breakthrough level
input int Shift=0; //horizontal shift of the indicator in bars
//+-----------------------------------+

This indicator was first implemented in MQL4 and published in Code Base at mql4.com on 08.10.2012

Fig.1 The AnchoredMomentum indicator