use on 1 or 2 min spx500
//@version=2
// works best on 1 or 2 min time frame
study("esspx")
n1=input(30,"ema1")
n2=input(120,"ema2")
sb=security("spx500" ,period , hl2 )
db=security("es1!" ,period , hl2 )
c=1000*db/sb
ao = sma(c,n1) - sma(c,n2)
plot(ao, color = change(ao) <= 0 ? green : green, style=histogram,linewidth=3)