Table:
|  |  | Year Ended December 31, |  |
| --- | --- | --- | --- |
|  | 2019 | 2018 | 2017 |
| Transaction Volume |  |  |  |
| Dollars (in millions) | $5,954 | $5,030 | $3,767 |
| Percentage increase | 18% | 34% |  |
| Loan Servicing Portfolio |  |  |  |
| Dollars (in millions, at end of period) | $9,150 | $7,341 | $5,390 |
| Percentage increase | 25% | 36% |  |
| Active Merchants |  |  |  |
| Number (at end of period) | 17,216 | 14,907 | 10,891 |
| Percentage increase | 15% | 37% |  |
| Cumulative Consumer Accounts |  |  |  |
| Number (in millions, at end of period) | 3.03 | 2.24 | 1.57 |
| Percentage increase | 35% | 43% |  |
Paragraphs:
ITEM 7. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (United States Dollars in thousands, except per share data and unless otherwise indicated)
Business Metrics
We review a number of operating and financial metrics to evaluate our business, measure our performance, identify trends, formulate plans and make strategic decisions, including the following.
Transaction Volume. We define transaction volume as the dollar value of loans facilitated on our platform
during a given period. Transaction volume is an indicator of revenue and overall platform profitability and has
grown substantially in the past several years.
Loan Servicing Portfolio. We define our loan servicing portfolio as the aggregate outstanding consumer loan balance (principal plus accrued interest and fees) serviced by our platform at the date of measurement. Our loan servicing portfolio is an indicator of our servicing activities. The average loan servicing portfolio for the years ended December 31, 2019, 2018 and 2017 was $8,213 million, $6,303 million and $4,501 million, respectively.
Active Merchants. We define active merchants as home improvement merchants and healthcare providers that have submitted at least one consumer application during the twelve months ended at the date of measurement. Because our transaction volume is a function of the size, engagement and growth of our merchant network, active merchants, in aggregate, are an indicator of future revenue and profitability, although they are not directly correlated. The comparative measures can also be impacted by disciplined corrective action taken by the Company to remove merchants from our program who do not meet our customer satisfaction standards.
Cumulative Consumer Accounts. We define cumulative consumer accounts as the aggregate number of consumer accounts approved on our platform since our inception, including accounts with both outstanding and zero balances. Although not directly correlated to revenue, cumulative consumer accounts is a measure of our brand awareness among consumers, as well as the value of the data we have been collecting from such consumers since our inception. We may use this data to support future growth by cross-marketing products and delivering potential additional customers to merchants that may not have been able to source those customers themselves.
Question:
How did the company define Loan Servicing Portfolio?
Answer: the aggregate outstanding consumer loan balance (principal plus accrued interest and fees) serviced by our platform at the date of measurement.