I think i was able to do this when the Security Challenge was available to me by looking at details or something, but I am unable to find anything like that currently. I don't see this detail available in the Security Dashboard, which seems to have replaced the Security Challenge.
Currently you can sort your Vault entries by Date Used, but not the date that the entry was created or last updated. I have passed this feedback along to our development team as well for consideration in future updates.
I've also just noticed this feature has been removed. Lastpass is telling me I have 330 old passwords but it's not even stated how "old" is defined. That's not very clever for a system that is supposed to be encouraging you to keep updating your passwords.
Please bump it up the list of priorities as it shouldn't take long to implement.
Add me to the list of folks miffed that this feature was removed with the new security dashboard. It would be less egregious if you never had the feature and we were asking for it but you had it and chose to remove it in giving us a nicer GUI for the dashboard. Bring display of age back. While changing every 30,60,90 is fading changing every 365 or so is still desired. I can't tell what passwords I've not touched in a long time. I can't see a reason to disable a feature like this.