I am using code referenced from the demostration algorithm near the botton of the below link. Other than some naming changes, the only major change between my code and the demostration code is that I added the percentage change logic in its own method so I can call it at a specified time of the day. 


I get the below error when I run the attached code:

`Runtime Error: In Scheduled Event 'EveryDay: SPY: 15 min after MarketOpen', AttributeError : 'VixAlgo' object has no attribute 'pct_change' AttributeError : 'VixAlgo' object has no attribute 'pct_change' (Open Stacktrace)`

My guess is that the scheduled event is being called before self.pct_change is calculated but I am not exactly sure how to confirm that, or what the fix would be if that were the case. Maybe make the scheduled event conditional? Any advice would be appreicated.