Help with removing products only with all zeros

Well! We do want to make sure we consider all products we sold in the past 10 years. This is refinement in Initial problem that was solved with the support of community (Link Here). So, if we sold product in 2012 and none thereafter. We would need to consider it when we look at Dec 2020 data because it was sold within last 10 years frame.

In the attached sample data, I have recreated reprex with modification to include values of BW in 2016 where we have sold a few of BW and none thereafter. So, if we are looking at 2018 and even if we have not sold any of BW in 2018, we would still like to retain all values of BW as we have sold a few in last 10 years.

We would like to delete the ones which we sold none in any of the years . This will help reducing the data before we can apply logic on addition of last 10 years sales (Link Here).

df <- data.frame(
  stringsAsFactors = FALSE,
              Date = c("2016-01-01","2016-02-01",
                       "2016-03-01","2016-04-01","2016-05-01","2016-06-01",
                       "2016-07-01","2016-08-01","2016-09-01","2016-10-01",
                       "2016-11-01","2016-12-01","2016-01-01","2016-02-01",
                       "2016-03-01","2016-04-01","2016-05-01","2016-06-01",
                       "2016-07-01","2016-08-01","2016-09-01","2016-10-01",
                       "2016-11-01","2016-12-01","2016-01-01","2016-02-01",
                       "2016-03-01","2016-04-01","2016-05-01","2016-06-01",
                       "2016-07-01","2016-08-01","2016-09-01","2016-10-01",
                       "2016-11-01","2016-12-01","2017-01-01","2017-02-01","2017-03-01",
                       "2017-04-01","2017-05-01","2017-06-01","2017-07-01",
                       "2017-08-01","2017-09-01","2017-10-01","2017-11-01",
                       "2017-12-01","2018-01-01","2018-02-01","2018-03-01",
                       "2018-04-01","2018-05-01","2018-06-01","2018-07-01",
                       "2018-08-01","2018-09-01","2018-10-01","2018-11-01",
                       "2018-12-01","2017-01-01","2017-02-01","2017-03-01",
                       "2017-04-01","2017-05-01","2017-06-01","2017-07-01",
                       "2017-08-01","2017-09-01","2017-10-01","2017-11-01",
                       "2017-12-01","2018-01-01","2018-02-01","2018-03-01",
                       "2018-04-01","2018-05-01","2018-06-01","2018-07-01",
                       "2018-08-01","2018-09-01","2018-10-01","2018-11-01",
                       "2018-12-01","2017-01-01","2017-02-01","2017-03-01",
                       "2017-04-01","2017-05-01","2017-06-01","2017-07-01",
                       "2017-08-01","2017-09-01","2017-10-01","2017-11-01","2017-12-01",
                       "2018-01-01","2018-02-01","2018-03-01","2018-04-01",
                       "2018-05-01","2018-06-01","2018-07-01","2018-08-01",
                       "2018-09-01","2018-10-01","2018-11-01","2018-12-01"),
           Product = c("TS","TS","TS","TS","TS",
                       "TS","TS","TS","TS","TS","TS","TS","BW","BW","BW",
                       "BW","BW","BW","BW","BW","BW","BW","BW","BW",
                       "FX","FX","FX","FX","FX","FX","FX","FX","FX","FX",
                       "FX","FX","TS","TS","TS","TS","TS","TS","TS",
                       "TS","TS","TS","TS","TS","TS","TS","TS","TS","TS",
                       "TS","TS","TS","TS","TS","TS","TS","BW","BW",
                       "BW","BW","BW","BW","BW","BW","BW","BW","BW","BW",
                       "BW","BW","BW","BW","BW","BW","BW","BW","BW",
                       "BW","BW","BW","FX","FX","FX","FX","FX","FX","FX",
                       "FX","FX","FX","FX","FX","FX","FX","FX","FX",
                       "FX","FX","FX","FX","FX","FX","FX","FX"),
             Sales = c(0,0,0,0,0,0,0,0,0,0,0,
                       0,1200,0,0,0,0,0,1800,0,0,0,0,0,0,0,0,0,
                       0,0,0,0,0,0,0,0,0,0,0,0,0,596,3476,4457,
                       4666,5967,10177,9475,6056,4302,6134,6676,8440,
                       10171,9182,8154,6006,5992,9028,7330,0,0,0,0,0,
                       0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
                       0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
                       0,0,0,0,0)
)

df <- df%>% 
  mutate(Date = ymd(Date))