Overdrive's Dollars & Sense columnist Kevin Rutherford explains how fuel-saving devices have to make a difference in at least one of four areas to be effective.
It was the fifth increase in the last six weeks, during which the diesel price has risen 16 cents.
The national average price increased 0.6-cent to $3.856 through Feb. 6.
The national average price increased 0.2-cent to $3.848 through Jan. 30. The latest price is 41.2 cents higher than a year earlier.
The national average price dipped 0.6-cent to $3.848 through Jan. 23.
The national average price increased 2.6 cents to $3.854 through Jan. 16.
Average diesel price jumped 4.5 cents to $3.828 through Jan. 9.
Over the last six weeks, the national price has dropped 22.7 cents.
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