SYMPTOM
In Strategy 10.x, 'Subscription deliveries' option is not available under Project Configuration->Statistics->General->Advanced Statistics Collection Options.
CAUSE
‘Prompt answer’, 'Subscription deliveries' and ‘Inbox messages’ under Project Configuration->Statistics->General->Advanced Statistics Collection Options are not available as separate options starting with Strategy Analytics Enterprise 10.0.0.
10.x view:

9.x view

ACTION
The above mentioned Statistics options are now merged under 'Basic Statistics'. Enabling Basic Statistics would also collect statistics regarding prompt answers, subscription deliveries and Inbox messages.