Sell opportunity in Corn calendar spread
The spread:
Its 5-10-15-20-30 year cycles seasonality:
Cot :
extended spread between commercials & speculators, also underlier is extended & its price starting to retract. 
Forward curve:
Volume analysis:
the volume profile is getting thin @ these level, not much volume traded relatively to lower prices
Historical price action of the spread : 
Backtesting of the spread: 
