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  • Problem: Invoicing deadline was missed 12 months in a row, causing revenue and expense analysis to be inaccurate
  • Root Causes Discovered: Customer walk-ins occupied staff and delayed invoice processing
  • Solution: A “work from home” day each month to remove the invoicing manager from walk-in interruptions
  • Results: Invoicing deadline has been met 100% of the time since improvements were implemented and the financial analysis is now current











Imagine trying to run an expanding business while not having an accurate analysis of the revenue and expenses. That’s the problem Rhea Health was facing month-to-month. An Oklahoma business started in 2006 and growing rapidly, Rhea Health provides workforce management health services to help companies promote safe, healthy, and productive work environments.

At Rhea Health, the deadline each month was to invoice customers by the 5th business day. This is an important deadline because it allows the business to close the monthly financial books and analyze business trends. It is also important that customers get their invoices consistently and quickly to pay their bills timely.

The problem was that Rhea Health had not made this deadline in any of the last 12 months. This issue ties into a larger effort the CEO was working on. He saw the need for reporting to be more accurate for revenue and expense analysis.

Solving the invoicing problem would enable reporting quickly after month closing, thus allowing for adjustments and quicker decision-making. A team, led by Tina Fuglestad, was formed to solve the invoicing problem. Tina led this project as part of her Lean Six Sigma Black Belt Training & Certification with GLSS.

The Root Causes

Early in the project, Tina and the team made some fascinating discoveries that ruled out some of their fundamental ideas on what was causing the missed deadlines. After learning how to conduct a Process Walk in the Green Belt Training & Certification, Tina guided the team to conduct one on the invoicing process. The team observed several problems that stopped or slowed down the invoicing process, including:

  • Customer pricing in the accounting software differed for the amounts in the invoicing process. The office manager had to manually change the amounts in the invoice entry process. The price was changed on the majority of invoices each month.
  • The email addresses housed in the system did not match the email where the invoices were supposed to be sent. This again required manual adjustment.
  • Customer walk-ins for unscheduled services completely stopped the process, causing major delays while staff served customers.

Tina recalls, “The office manager voiced previously that her biggest concern about completing invoices on time was the environmental interruptions from customers. Taking care of the customer is and always will be the priority. But this meant delays with invoicing.”

As part of the Lean Six Sigma Black Belt Training & Certification, Tina learned Hypothesis Testing and Regression Analysis. Tina decided Regression Analysis would be helpful in confirming the root causes identified from the Process Walk. With the analysis, the team looked for evidence of a cause-and-effect relationship between late invoicing and factors such as email addresses changes, pricing differences, staff PTO, and walk-in customers.

The analysis was clear: email changes, staff PTO, and pricing differences—while tedious—were not causing the invoicing delay. However, the customer walk-in impact was clear. The graph below shows that as the number of walk-ins increases, the number of days to complete invoicing increases.

Tina reflects on a key lesson from the project:

“Our office manager had the feeling that customer interruptions were the root cause of invoice completion delay, but it was nice to be able to back up her feelings with facts based on our data. Our analysis offered compelling proof that the customer walk-in interruptions were delaying invoice completion by 5-15 days. We were able to validate her feelings with the facts and enact a process change that made all parties happy.”

The Solutions

“Knowing customer walk-ins were the root cause, we determined the best solution was to implement a work-from-home day for the office manager to allow her to complete the invoice entry process. This eliminated the outside environmental forces that were causing delays in completion. The GLSS training provided the tools that enabled us to work together and create a complete solution,” reflects Tina.

The team put processes in place to eliminate any issues that could arise from the work-from-home day. For example:

  • Monitoring the company schedule to ensure the staff can handle the customer walk-in workload with the manager away and maintain the level of service provided in the past
  • Ensuring invoice paperwork is organized for the work-from-home day
  • Maintaining constant communication between the staff and office manager so that quick action could be taken on any other factors that may come up
  • Monitoring the number of walk-ins during the last and first days of the month to determine when to schedule the work-from-home day

“The GLSS training helped us apply the tools and enabled our success. I liked the independence of the training. It let me work at my own pace and fully understand the content. The examples were clear and easy to follow. The case study tied it all together. When I had questions, GLSS was very supportive and answered quickly,” Tina summarizes.

The Results

“Since implementing our solution, we have met the deadline for three consecutive months and expect to see these positive results moving forward,” Tina states.

At the time of this article, Rhea Health has sustained its 100% on-time performance. They not only meet the deadline each month, but are typically 3 to 4 days early!

Rhea Health has sustained its 100% on-time performance. They not only meet the deadline each month, but are typically 3 to 4 days early!

Now the CEO is able to see the positive effects of getting invoices completed by the deadline. He can pull monthly reports quickly and make quicker decisions based on more complete data on revenue and expense.

Rhea Health is hearing positive feedback from customers for receiving their invoices consistently at the beginning of the month, which positively impacts their accounts payable and reporting. Also, with the improved planning, walk-in customers are receiving better service and providing positive feedback.