36% of those units, circled in green below, are in the Potrero Hill/Dogpatch/Mission Bay neighborhoods. 1,522 units are in the Potrero/Showplace Square/Dogpatch neighborhood and another 1,063 in Mission Bay.
The other big concentration is in the SOMA/Rincon area.
Keep in mind, these are projects that were first proposed to the city's Planning Department three to five years ago (2011-2013). That's how long it generally takes from initial filing to final completion assuming 1-2 years for actual construction.