Why facebook custom audience size column always showing two hyphens

Question

I am using graph api v2.8 and have created website custom audience using following code.

$audience->setData(array(
                  CustomAudienceFields::NAME            => $associative_arr['name'],
                  CustomAudienceFields::PIXEL_ID        =>    $associative_arr['pixelId'],
                  CustomAudienceFields::DESCRIPTION     => $associative_arr['description'],
                  CustomAudienceFields::RETENTION_DAYS  => $associative_arr['retensionDays'],  
                  CustomAudienceFields::SUBTYPE         => CustomAudienceSubtypes::WEBSITE,
                  CustomAudienceFields::RULE            => array('url' => array('i_contains' => $associative_arr['websiteUrl'])),
                  CustomAudienceFields::PREFILL         => $associative_arr['prefill'],
                  CustomAudienceFields::DATA_SOURCE     => array('EVENT_BASED' => 'ANYTHING')
                ));         
    $audience->create();

But I can notice even after 900 pixel fires. It is showing size "--" and availability "Audience too small". I have tried with custom audience as well and manually added users in it with first, last name and email addresses.

So just want to know why size is not updating and what is the difference between size and availability columns?

Answer 1

From https://developers.facebook.com/docs/marketing-api/reference/custom-audience#Creating, you can see that to create a website custom audience, the min size is 200. If the pixel has fired for 900 times, you might have like actually 85 unique people, for example, and among which 70 of them are Facebook users, for example. That is too small.

"--" instead of a real name is something done by Facebook on purpose: when the number is too small, the actual number is not shown. Otherwise, you can trick someone to go to your website, and by checking the custom audience size 1 or 0, you would know whether that person has a Facebook account. That would be an information leak.

The difference between size and availability? One is a number and one is a status. Too many differences. When the number is too small, you see "--". Otherwise, it would be a number.