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The U.S. economy has grown just 1.5 percent in the 2014 fiscal year - far slower than White House projections - while more than $500 billion of deficit spending was added to the national debt, according to new projections released today by the non-partisan Congressional Budget Office.

Just last month the Obama administration optimistically forecast 2.6 percent GDP growth in 2014.

The CBO had some good economic news, predicting that the GDP will rebound and expand by 3.4 percent over the next two years due to increased demand for goods and services, businesses investments in new structures and equipment, improved consumer spending and good news on the housing front.

In its report released today, the CBO said growth was stymied in fiscal year 2014 partly by "bad weather" during the cold months of spring.

The report said that $506 billion was added to the national debt this year, but that was almost $170 billion less than last year. The CBO also estimated the annual deficit will shrink to $459 billion in 2015 if taxes and spending law remains the same. But the deficit would rapidly grow in years to follow, hitting a ceiling of $960 billion by 2024 unless Congress enacts changes to alter the trajectory.

In total, CBO says current law would create $7.2 trillion in unfunded liabilities over the next 10 years.

CBO's latest data also predicts the national unemployment rate will average 5.6 percent from 2018 through 2024.