How is the "custom date" field populated? What value does it show on that same lead? Try to update it manually on one lead and see whether the Form Date is correct. It will prove that the formula works.
Now, Marketo may no like the idea of concatenating a string with a date field, and that might be the issue. You might want to set the "Custom Date" field to be a string field instead.
Create a campaign triggered upon form fill out, will change the program status of the lead to "Fills Out Form" or something more relevant.
Now, after you get a few form fills, go into the Members tab. You'll see the member's name, you'll see "Changed Program Status" and the date is happened. Voila!
We initially used the custom field approach, but that didn't work for us. This is because our leads can fill out forms multiple times per year (such as a returning lead x months later), and we are interested with each instance of dates (as opposed to the original or most recent).
Our solution was to tie in Google Analytics/Adwords into the submit button, which date/time stamps each form fill out regardless of the number of times they return. In essence, I can see if "jane doe" filled out a form in January and again in April. Marketo doesn't offer an adequate solution for this.
We initially used the custom field approach, but that didn't work for us. This is because our leads can fill out forms multiple times per year (such as a returning lead x months later), and we are interested with each instance of dates (as opposed to the original or most recent).
That's what history fields are for -- they don't get overwritten but rather appended.
In essence, I can see if "jane doe" filled out a form in January and again in April. Marketo doesn't offer an adequate solution for this.
What exactly are the parameters you want to pass to a report? Having trouble imagining a GA-based solution for Known Leads that could possibly be usable at scale (unless you are also using GA UserID and bringing things together in a separate analytics database).
We were interested in counting the number of inquiries. In a simple scenario, suppose the same 1 lead fills out a form every week for the month of January.
If I setup a report for January based on a token/custom-field relationship, Marketo would reveal 1 inquiry (be it original datestamp, most recent, or other). It would not export 4 rows for a single lead in a csv with each date (or date1, date2, date3, date4 columns).
If I do setup a list querying for this information, I would need to alter my filter 31 times for the 31 days to find out when. While I would then know the 4 dates/inquiries, this is not scaleable.
As you guessed, our solution was to join ga uid and a few other dimensions/metrics into another database alongside Marketo; We can now see the known lead from marketo as well as the number of times they interacted with a form and, more importantly, all the associated dates en masse.
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