The simple cumulative daily return is calculated by taking the cumulative product of the daily percentage change. This calculation is represented by the following equation:
![](/api/v2/epubs/9781787123137/files/assets/bceee955-b77e-4411-a3f7-38311c9e8694.png)
This is calculated succinctly using the .cumprod() method:
![](/api/v2/epubs/9781787123137/files/assets/cdd02e58-ca2b-4bf7-9e76-c377e906849d.png)
It is now possible to plot cumulative returns to see how the various stocks compare in value over time:
![](/api/v2/epubs/9781787123137/files/assets/0cf06486-8829-4821-b816-b1e8f504af6e.png)