Unit rates and unit ratios. A unit rate is a ratio that has a denominator of 1. A unit rate is also called a unit ratio. (They mean the same thing.). $\frac{5}{4}$ and $3:8$ and $40\mbox{ to }10$ are ratios, but they are not unit ratios. $\frac{1.25}{1}$ and $0.375:1$ and $4\mbox{ to }1$ are unit ratios. unit rate is also called a unit ratio. (They mean the same thing.). $\frac{5}{4}$ and $3:8$ and $40\mbox{ to }10$ are ratios, but they are not unit ratios.
I found the following references to Coca-Cola Zero launching in the US in 2005: 1  Associated Press March 21, 2005 announcement that the product would launch in June - http://www.nbcnews.com/id/725792...  Case study by ATTIK, which provided worldwide branding services, citing a 2005 launch - ATTIK.
It was first introduced in the United States on August 9, 1982, as the first new brand since 1886 to use the Coca-Cola Trademark. Today, Diet Coke/Coca-Cola light is one of the largest and most successful brands of The. Company, available in more than 185 markets around the world.