Time series / forecasting

Hi all

I’m working on a time series problem (in some ways its very similar to Rossman).

My mission is to predict the price over time. Like you can see in the graph below - its very sensitive to the date.

**My Question **: How can I “force” the model to be more sensitive to date? I want it to have much more Influence on the data.

image

If you want to compare this problem to the Rossman competition so you can think about this graph as a graph for one store. (this problem comes back at every “store”)

thanks!
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