I have 3 year's worth of revenue build-up data (52 weeks, weekly) from 2015 - 2018. So, it is a revenue build-up curve on a yearly basis.
Hypothetically, if I have one single data point in the future, say 4 weeks into 2019, can I do time series taking this extra data point that I have into account? Can I "join"/predict the beginning week of 2019 to the 4th week of 2019 (data pt that I have) somehow? (short of drawing a straight line to the future data pt)
Is there something like this? I'm exploring rnn, arima, prophet but none of them seems to be able to cater for this.
The only method I can think of is to use regression, but this didn't give me satisfactory results, it's under-predicting by a lot.
Looking for some ideas on how to model this.