Update on "The Bernie Effect" in Whatcom County

New or reactivated registrations are increasingly younger and more urban in Whatcom County. Click to Enlarge.

Density Curves. Left: Birth Years of Voters who have left the voter rolls in the last 17 months. Right: Birth Year of Voters who have joined voter rolls in the last 17 months. Click to Enlarge.

4,962 net voters have been added to the Whatcom County voting rolls in the last 17 months. 12,428 voters have left or been marked inactive. 17,390 have registered themselves as active. (Yes. That is stupendous number for Whatcom County.) We are adding almost 10 registrants per day.  These registrants would be a mix of original registrations and re-activations  or address changes. The last 17 months have been responsible for 3.9% increase in the voter database since 11/22/2014.
Code here.
(mdy("04/15/2016") - mdy("11/22/2014"))
Time difference of 510 day between rNA2014 and rNA2016:

length(rNA2014$RegistrationNumber) # Active voters as of 11/22/2014
 127211
length(rNA2016$RegistrationNumber) # Active voters as of 04/15/2016
 132173

# Voters from 11/2014 in/not in 4/2016
count(data.table(rNA2014$RegistrationNumber %in% rNA2016$RegistrationNumber),V1);
Source: local data table [2 x 2]

     V1      n
  (lgl)  (int)
1  TRUE 114783
2 FALSE  12428

# Voters from 4/2016 in/not in 11/2014
count(data.table(rNA2016$RegistrationNumber %in% rNA2014$RegistrationNumber),V1);
Source: local data table [2 x 2]

     V1      n
  (lgl)  (int)
1 FALSE  17390
2  TRUE 114783

132173 - 127211  # net change between dates
4962

17390 - 12428     # also net change between dates: 17,390 gained 12,428 lost
4962

(mdy("04/15/2016") - mdy("11/22/2014"))
# Time difference of 510 days

4962/510 # net change over time / number of days
9.729412 # Adding almost 10 registrants per day!

4962/17 # net change over time / number of months
291.8824# Adding 292 registrants each month!

# Depending on past/present viewpoints:
# The last 17 months have been responsible for 3.75% in existing the voter database

(4962/132173) * 100
3.754171

# The last 17 months have been responsible for 3.9 increase in the voter database since 11/22/2014

(4962/127211) * 100
 3.900606