Developed at Wagner's request at a time when the technical capabilities of modern brass instruments were being expanded, it enabled him to fill a gap in tone color between the mellow lyricism of the horns and the penetrating brilliance of the trombones.

WSJ: It Takes Brass to Play the Wagner Tuba | By Barbara Jepson | The Ring of the Nibelung

For women of color, the gap is even wider: African American women earn 66.5 cents and Latina women only 56.7 cents to the dollar earned by men.

FORBES: Equal Pay Day: 'Celebrate' By Spreading The Word

And the White House also notes that families of color are closing the homeownership gap with whites.

NPR: Is Housing Market Squeezing Out the Middle Class?