Hex #999500 or rgb(153,149,0) in RGB space is the tint of yellow. It has hue angle of 58.43 degrees, value = 60 and saturation = 100. #999500 can be obtained by mixing 4 colors: 4 drops of yellow, 2 drops of red, 3 drops of green, 1 drop of black.
Nearest safe hex - #999900. Below you can see the block with #999500 color and its structure: in procentage ratio and in drops of pigments. Click "TRY" button to move #999500 to the mixer and play with it.