This indicators package will help you find an count Elliott Waves. They are based on Williams%R, 5 period or 10 period or 15 period.

Explanation from the original topic on forum:
It happens some years ago Elliott Wave International’s chief commodity analyst and “Futures Junctures Service” editor Jeffrey Kennedy” presented his Trend Analyzing Tool in a webinar. On Tuesday, 22 December 2009, EWI disclosed the formula to the public on their website.

JK Fast Line measures the most immediate, near-term progression of a market’s trend and smallest degree of the Elliott wave structure.

JK Base Line measures the intermediate progression of a market’s trend.
JK Slow Line (not show on screen shot) measures the long-term progression of a market’s trend.

In the original JK_TA each panel of the indicator consists of three lines: a 5-period %R, a 10-period %R and a 15-period %R of the line concerned.
A reading of 100 indicates an uptrend. A reading of 0 indicates a downtrend.

The JK TA as such is as a proxy for clarifying the underlying Elliott wave structure:

When all three lines in any version are flatlining (blended into one), it signals an impulsive, or motive, structure. See the blue lines in screen shot.
On the other hand, anytime you see the three lines separate, it’s a strong signal that the market is yielding a countertrend, or corrective pattern.

The JK_TA can be used on any instrument and on any time frame:
The first, second and third chart depict the basic indicator for different time frames. The fourth chart shows a custom variant of JK_TA: the Fast, Base and Slow lines packed together in one panel, selectable by the 5%R, 10%R or 15%R version of the three indicators.

https://www.prorealcode.com/topic/jeffrey-kennedy-trend-analyzer/

Combo indicator: (all indicators can be downloaded also separately at the end of this post).

//JKFast

fastLength=5
slowLength=20

valuefast=ExponentialAverage[fastlength](close)-ExponentialAverage[slowlength](close)

hv5 = Highest[5](valuefast)
lv5 = Lowest[5](valuefast)

if hv5 = lv5 then
JKFast5=0
else
JKFast5=((hv5 - valuefast) / (hv5 - lv5) * (-100) + 100)
endif

hv10 = Highest[10](valuefast)
lv10 = Lowest[10](valuefast)

if hv10 = lv10 then
JKFast10=0
else
JKFast10=((hv10 - valuefast) / (hv10 - lv10) * (-100) + 100)
endif

hv15 = Highest[15](valuefast)
lv15 = Lowest[15](valuefast)

if hv15 = lv15 then
JKFast15=0
else
JKFast15=((hv15 - valuefast) / (hv15 - lv15) * (-100) + 100)
endif

//JK TA

valuebase=ExponentialAverage[fastlength](close)

hv5 = Highest[5](valuebase)
lv5 = Lowest[5](valuebase)

if hv5 = lv5 then
JKTA5=0
else
JKTA5=((hv5 - valuebase) / (hv5 - lv5) * (-100) + 100)
endif

hv10 = Highest[10](valuebase)
lv10 = Lowest[10](valuebase)

if hv10 = lv10 then
JKTA10=0
else
JKTA10=((hv10 - valuebase) / (hv10 - lv10) * (-100) + 100)
endif

hv15 = Highest[15](valuebase)
lv15 = Lowest[15](valuebase)

if hv15 = lv15 then
JKTA15=0
else
JKTA15=((hv15 - valuebase) / (hv15 - lv15) * (-100) + 100)
endif

//JK Slow

valueslow=ExponentialAverage[slowLength](close)

hv5 = Highest[5](valueslow)
lv5 = Lowest[5](valueslow)

if hv5 = lv5 then
JKSlow5=0
else
JKSlow5=((hv5 - valueslow) / (hv5 - lv5) * (-100) + 100)
endif

hv10 = Highest[10](valueslow)
lv10 = Lowest[10](valueslow)

if hv10 = lv10 then
JKSlow10=0
else
JKSlow10=((hv10 - valueslow) / (hv10 - lv10) * (-100) + 100)
endif

hv15 = Highest[15](valueslow)
lv15 = Lowest[15](valueslow)

if hv15 = lv15 then
JKSlow15=0
else
JKSlow15=((hv15 - valueslow) / (hv15 - lv15) * (-100) + 100)
endif

Return JKFast5 coloured (255,150,255) as "JKFast5", JKFast10 coloured (255,100,255) as "JKFast10", JKFast15 coloured (255,50,255) as "JKFast15", JKSlow5 coloured (150,200,0) as "JKSlow5", JKSlow10 coloured (100,200,0) as "JKSlow10", JKSlow15 coloured (50,200,0) as "JKSlow15", JKTA5 coloured (150,150,255) as "JKTA5", JKTA10 coloured (100,100,255) as "JKTA10", JKTA15 coloured (50,50,255) as "JKTA15"