WFAA breaks down the math behind North Texas Tollway Authority finances and looks at both the authority’s structured debt and its plans to spend $1 billion on future projects. “Approximately 19 percent ($125.6 million) of what customers paid in tolls last year is allocated to the Capital Investment Fund Deposit. Some of the planned projects include widening the Dallas North Tollway and a whole new tolled section of Highway 360 south of Interstate 20 expected to be completed next year. . . .”