A question about Amsterdam in 1900

[David Patte]

  I was reviewing some historical zones & rules, and I can across a date 
for Amsterdam that has me a bit confused.

I'm not sure if I'm misinterpreting the records, or whether a record is 
missing.

Lets take Jan 1, 1900 for Amsterdam.

The Zone table for Europe/Amsterdam shows:

a GMT offset of 0:19:32 (and no rule) until 1835, then
a GMT offset of 0:19:32 (and Neth rule) until July 1 1937 - using '%s' 
for letters

So for Jan 1, 1900 I am assuming I should be looking for a rule in the 
Neth rules records

But the first 'Neth' Rule starts 1916.

I can easily easily understand that this means that there is no special 
save amount to apply on Jan 1st 1900, but what letters should I be using 
for that date given that the zone says the letters should be %s?

Since the zone record says '%s' for that date, should there not be a 
rule record starting in 1835 that gives a save amount of 0, and provides 
the letters 'AMT'?

Thanks