From the website: "The National Popular Vote law has been enacted by states possessing 132 electoral votes — 49% of the 270 electoral votes needed to activate it."
From Wikipedia, for additional explanation: "The agreement is to go into effect only when the participating states that have joined the compact together have an absolute majority in the Electoral College. . . . Until the compact is joined by states with a majority of electoral votes, all states will continue to award their electoral votes in their current manner."
I initially thought that the first quote was saying that the national popular vote had gotten to 49% of the 50% of the total pool of electoral votes needed to activate it, but no, that's not what it says. It currently has about 24.5% of the total pool of electoral votes.