# What does a straight line of residuals of a time series mean?

I used Python's statsmodels' seasonal_decompose & received the following plots:

I understand that the residuals here are what is leftover after trend & seasonality are removed, but is there anything I can interpret from a straight line of residuals between 0.95 & 1.00? Also, my data started on 03/01/2019 & ended on 03/01/2020. Why don't my trend & residuals plots start & end at those same dates?

• It is one manifestation of the inability to detect seasonality with fewer than two full seasons of data. It is helpful to pay attention to the different scales on the vertical axes here: the bottom two plots are essentially tiny amounts of noise. – whuber Apr 12 at 16:14
• i see, thank you for your help! – M_Neelakandan Apr 13 at 2:19