23 of 32 NFL teams converted 50% or higher of their fourth down conversion attempts in 2018.
The Baltimore Ravens are going to set the NFL record for most attempted fourth down conversions (the browns set the record with 31) and convert the most fourth downs in NFL history (the 2017 eagles converted 17 in 2017).
That means the Ravens will be at least 18 of 32.
The NFL has been trending towards more fourth down conversions for years, as analytics and statistical analysis has become more commonplace.