Calculating ROI (Return on Investment) is based on a simple formula involving the gain from an investment, the cost of the investment and the resulting ROI. Here it is:

Yet, to many, it is one of the most desired but vexing business measurements. Why?

Here are the 10 most common mistakes businesses make in calculating ROI.

1. CONFUSION BETWEEN CASH FLOW AND GAINS: A common mistake in calculating ROI is comparing the initial investment, which is always in cash, with the gain as measured by profit or (in some cases) revenue. And not basing the gain on cash flow. For example, customers might be billed but that doesn’t mean they all pay on time. Or shipments might have gone out. But some goods might have been returned. The correct approach is always to base the gain, either profits or revenue, on the cash flow received.
2. UNDERESTIMATE INITIAL COSTS: Many businesses try calculating ROI without first properly accounting for all initial costs. As a result, they may end up underestimating initial costs. Before you start your calculations, know what your initial costs are. Here are some of the areas that might be missed.
3. FAIL TO INCLUDE PEOPLE’S TIME: One of the reason ROI is a highly regarded measurement is it includes not just out-of-pocket costs but operational costs like labor. Most business owners are aware that time is money for any company. However, when it comes to calculating ROI, they forget to consider the value of their time or that of their employees.
4. DON’T KNOW THE MINIMUM RETURN REQUIRED: Take into consideration the minimum ROI that your company requires because there probably is one. Look at the relative risks, cost of capital, and opportunity costs. Here’s what experts say is a good ROI for various industries. Even if it hasn’t been formally stated, have the discussion to bring it out when you start calculating ROI.
5. MEASURE THE WRONG THING: In 2010, Pepsi launched the Pepsi Refresh Project, an initiative where people could submit and vote for their favorite nonprofit projects to receive grants from Pepsi. The project generated 3.5 million Facebook likes, 60,000 Twitter followers, and over 80 million votes for nonprofits. But it didn’t sell more Pepsi. Pepsi cancelled the project in 2012 after falling from second to third place in national soda market share. It was a noble initiative, but likes, followers and votes were not the right measurements for ROI.
6. MEASURE TOO MANY THINGS: In data-rich environments, it’s easy to lose sight of the metrics that really matter. Before calculating ROI, know the Key Performance Indicators (KPIs) for your business. KPIs are the metrics that matter for any business. They are metrics that, just like your ROI, have a target. If you don’t know them, you may find yourself measuring too many things.
7. DON’T LEVERAGE EXISTING CAPABILITIES: A manager at a large wireless telecommunications firm recently called for help with her budget. She’d “taken a stab” at quantifying the ROI for the company’s data warehouse and wanted to review her calculations. Her worksheet—which included a rigorous mix of hardware, software licenses, maintenance, burdened staff, and consultant costs, etc.—made clear that she’d forgotten an important step: Leverage current IT infrastructure and resources to reduce cost estimates and make a project more attractive to business executives.
8. DON’T GET THE BUSINESS TEAM INVOLVED: No one wants to own ROI. Calculating ROI can be difficult; understanding all the required skill and resource components can challenge even the best manager. When the planning phase of a project occurs, most managers take it upon themselves to calculate ROI on their own. It’s important that baseline ROI numbers are adopted by a team and accepted by the key business stakeholders.
9. DON’T ACCOUNT FOR THE FULL SALES CYCLES: In the B2B buying process, it can take many months for a prospect to go from first touch to closed sale. If you try to calculate your ROI too soon, you may undervalue the amount of impact that investments are making. In the B2C buying process, it may take time to generate awareness, educate consumers and gain trial. But, once you do, buying frequency might increase at that point. Pick a time period to measure your ROI that makes the most of the resources invested.
10. DON’T ACCOUNT FOR CHANGE: Nothing is certain. You can’t know what competitive developments, new trends or surprises might occur during the measurement period for your ROI. So don’t treat ROI as an area that you “set and forget.” Look at it regularly. Evaluate against KPIs. And be prepared to make revisions as necessary. Anything worth measurement should be view with the most current data.

Do these mistakes help you to understand the correct way to calculating ROI. Does your business need help in doing and managing ROI.