Explorer 2 Low amplitude

[jimi]

Hello!
I haven't posted in a long time.
I just got a timegrapher and tested my watches.
On my 5-year old Explorer 2 (16570/3185), fully wound, I didn't get an amplitude of more than 270 on any positions. Dial-up gave the highest reading of 265-270 and varies from 220-250 on other positions. Other parameters: beat error= 0.0 - 0.2, 0 to -4 secs/day variation in most positions. Lift angle set at 54*.
This watch has not been serviced but was regulated at second year as it was running +7/day.
Right now, it's running at -1.4secs/day (2-wk average).
Should I be worried with these results?
Thank you in advance.