Use the show ntp statistics command to view the output for each NTP stratum regardless of whether authentication is enabled.
Switch:1#show ntp statistics
NTP Server : 192.0.2.187
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Stratum : 16
Version : NTPv4
Broadcast : No
Auth Enabled : Disabled
Auth Status : Not-Auth
Sync Status : Rejected
Reachability : Unreachable
Root Delay : 0.000
Root Disp : 0.000
Delay : 0.000
Dispersion : 15937.500
Offset : 0.000
Precision : -23
Jitter : 0.000
Last Event : Mobilize
NTP Server : 192.0.2.201
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Stratum : 4
Version : NTPv4
Broadcast : No
Auth Enabled : Enabled
Auth Status : Ok
Sync Status : Candidate
Reachability : Reachable
Root Delay : 18.448
Root Disp : 128.677
Delay : 18.448
Dispersion : 0.366
Offset : 0.202
Precision : -24
Jitter : 1.041
Last Event : Popcorn