Relationship between length of CFTID and the number of points in geometry

select 
  len(_CFTID), avg(GEOMETRY_BIN.STNumPoints())
  from
  [PARCEL_DATA].[dbo].[ParcelDetail]
  where
  _CFTID like '03200012%'
  group by
  LEN(_cftid)
  order by
  LEN(_cftid)

Len     NumPoints
10       199826
11       969
12       16
13       33
14       380
15       30
16       18
17       17
18       10
19       8
20       6
21       10