Liquidity Our primary sources of cash include receipts of premiums, administrative services fees, investment income, and proceeds from the sale or maturity of our investment securities and from borrowings.
Our primary uses of cash include disbursements for claims payments, administrative expenses, interest expense, and taxes, purchases of investment securities and capital expenditures and payments on borrowings.
Cash and cash equivalents decreased to $580.1 million at December 31, 2004 from $931.4 million at December 31, 2003.
The change in cash and cash equivalents for the years ended December 31, 2004, 2003 and 2002 is summarized as follows:
## Table 0 ##
Cash Flow from Operating Activities Our operating cash flows in 2004 were significantly impacted by the timing of the Medicare Advantage premium remittance which is payable to us on the first day of each month.
When the first day of a month falls on a weekend or holiday, we have historically received this payment at the end of the previous month.
As such, the Medicare Advantage receipts for January 2004 of $211.9 million and January 2003 of $205.8 million were received in December 2003 and December 2002, respectively, because January 1 is a holiday.
This timing accounts for a significant portion of the unearned revenues balance on our consolidated balance sheet at December 31, 2003.
Beginning in 2005, the monthly premium payment schedule includes a change in timing from previous practice.
As a result of this change, the January 2005 payment of $290.3 million originally scheduled to be received on Friday, December 31, 2004, was changed to Monday, January 3, 2005, or one business day later.
Therefore, we received only 11 monthly Medicare Advantage premium remittances during 2004 versus 12 monthly premium remittances during 2003.
Other than the impact from the timing of the Medicare Advantage premium receipts, the increase in net income and cash generated from changes in working capital increased our operating cash flow in 2004 compared to 2003.
The most significant drivers of changes in our working capital are typically the timing of receipts for premiums and administrative services fees and payments of medical expenses.
We illustrate these changes with the following summary of receivables and medical and other expenses payable.
The detail of total net receivables was as follows at December 31, 2004, 2003 and 2002:
## Table 1 ##
consistently reliable result.
Conversely, for the most recent three months of incurred claims, the volume of claims processed historically is not at a level sufficient to produce a reliable result, which therefore requires us to examine historical trend patterns as the primary method of evaluation.
Changes in claim processes, including receipt cycle times, claim inventory levels, recoveries of overpayments, outsourcing, system conversions, and processing disruptions due to weather or other events affect views regarding the reasonable choice of completion factors.
The receipt cycle time measures the average length of time between when a medical claim was initially incurred and when the claim form was received.
Increased electronic claim submissions from providers have decreased the receipt cycle time over the last few years.
For example, the average receipt cycle time has decreased from 16.5 days in 2005 to 15.6 days in 2007 which represents a 5.5% reduction in cycle time over the three year period.
Medical cost trends potentially are more volatile than other segments of the economy.
The drivers of medical cost trends include increases in the utilization of hospital facilities, physician services, prescription drugs, and new medical technologies, as well as the inflationary effect on the cost per unit of each of these expense components.
Other external factors such as government-mandated benefits or other regulatory changes, increases in medical services capacity, direct to consumer advertising for prescription drugs and medical services, an aging population, catastrophes, and epidemics also may impact medical cost trends.
Internal factors such as system conversions, claims processing cycle times, changes in medical management practices and changes in provider contracts also may impact our ability to accurately predict estimates of historical completion factors or medical cost trends.
All of these factors are considered in estimating IBNR and in estimating the per member per month claims trend for purposes of determining the reserve for the most recent three months.
Additionally, we continually prepare and review follow-up studies to assess the reasonableness of the estimates generated by our process and methods over time.
The results of these studies are also considered in determining the reserve for the most recent three months.
Each of these factors requires significant judgment by management.
The completion and claims per member per month trend factors are the most significant factors impacting the IBNR estimate.
The portion of IBNR estimated using completion factors for claims incurred prior to the most recent three months is less variable than the portion of IBNR estimated using trend factors.
The following table illustrates the sensitivity of these factors assuming moderate adverse experience and the estimated potential impact on our operating results caused by reasonably likely changes in these factors based on December 31, 2007 data:
## Table 2 ##
(a) Reflects estimated potential changes in benefits payable caused by changes in completion factors for incurred months prior to the most recent three months.
(b) Reflects estimated potential changes in benefits payable caused by changes in annualized claims trend used for the estimation of per member per month incurred claims for the most recent three months.
Humana Inc.  NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—(Continued) 3.
ACQUISITIONS On December 21, 2010, we acquired Concentra Inc. , or Concentra, a health care company based in Addison, Texas, for cash consideration of $804.7 million.
Through its affiliated clinicians, Concentra delivers occupational medicine, urgent care, physical therapy, and wellness services to workers and the general public through its operation of medical centers and worksite medical facilities.
The Concentra acquisition provides entry into the primary care space on a national scale, offering additional means for achieving health and wellness solutions and providing an expandable platform for growth with a management team experienced in physician asset management and alternate site care.
The preliminary fair values of Concentra’s assets acquired and liabilities assumed at the date of the acquisition are summarized as follows:
## Table 3 ##
The other intangible assets, which primarily consist of customer relationships and trade name, have a weighted average useful life of 13.7 years.
Approximately $57.9 million of the acquired goodwill is deductible for tax purposes.
The purchase price allocation is preliminary, subject to completion of valuation analyses, including, for example, refining assumptions used to calculate the fair value of other intangible assets.
The purchase agreement contains provisions under which there may be future consideration paid or received related to the subsequent determination of working capital that existed at the acquisition date.
Any payments or receipts for provisional amounts for working capital will be recorded as an adjustment to goodwill when paid or received.
The results of operations and financial condition of Concentra have been included in our consolidated statements of income and consolidated balance sheets from the acquisition date.
In connection with the acquisition, we recognized approximately $14.9 million of acquisition-related costs, primarily banker and other professional fees, in selling, general and administrative expense.
The proforma financial information assuming the acquisition had occurred as of January 1, 2009 was not material to our results of operations.
On October 31, 2008, we acquired PHP Companies, Inc.  (d/b/a Cariten Healthcare), or Cariten, for cash consideration of approximately $291.0 million, including the payment of $34.9 million during 2010 to settle a purchase price contingency.
The Cariten acquisition increased our commercial fully-insured and ASO presence as well as our Medicare HMO presence in eastern Tennessee.
During 2009, we continued our review of the fair value estimate of certain other intangible and net tangible assets acquired.
This review resulted in a decrease of $27.1 million in the fair value of other intangible assets, primarily related to the fair value assigned to the customer contracts acquired.
There was a corresponding adjustment to goodwill and deferred income taxes.
The

Tables referenced above, in order (Table 0 first):
<table><tr><td></td><td>2004</td><td>2003</td><td>2002</td></tr><tr><td></td><td colspan="3">(in thousands)</td></tr><tr><td>Net cash provided by operating activities</td><td>$347,809</td><td>$413,140</td><td>$321,408</td></tr><tr><td>Net cash used in investing activities</td><td>-624,081</td><td>-382,837</td><td>-204,974</td></tr><tr><td>Net cash (used in) provided by financing activities</td><td>-75,053</td><td>179,744</td><td>-46,497</td></tr><tr><td>(Decrease) increase in cash and cash equivalents</td><td>$-351,325</td><td>$210,047</td><td>$69,937</td></tr></table>
<table><tr><td></td><td></td><td></td><td></td><td colspan="2">Change</td></tr><tr><td></td><td>2004</td><td>2003</td><td>2002</td><td>2004</td><td>2003</td></tr><tr><td></td><td colspan="5">(in thousands)</td></tr><tr><td>TRICARE:</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Base receivable</td><td>$396,355</td><td>$266,656</td><td>$197,544</td><td>$129,699</td><td>$69,112</td></tr><tr><td>Bid price adjustments (BPAs)</td><td>25,601</td><td>92,875</td><td>104,044</td><td>-67,274</td><td>-11,169</td></tr><tr><td>Change orders</td><td>6,021</td><td>7,073</td><td>57,630</td><td>-1,052</td><td>-50,557</td></tr><tr><td></td><td>427,977</td><td>366,604</td><td>359,218</td><td>61,373</td><td>7,386</td></tr><tr><td>Less: long-term portion of BPAs</td><td>—</td><td>-38,794</td><td>-86,471</td><td>38,794</td><td>47,677</td></tr><tr><td>TRICARE subtotal</td><td>427,977</td><td>327,810</td><td>272,747</td><td>100,167</td><td>55,063</td></tr><tr><td>Commercial and other</td><td>186,144</td><td>178,577</td><td>146,882</td><td>7,567</td><td>31,695</td></tr><tr><td>Allowance for doubtful accounts</td><td>-34,506</td><td>-40,400</td><td>-30,178</td><td>5,894</td><td>-10,222</td></tr><tr><td>Total net receivables</td><td>$579,615</td><td>$465,987</td><td>$389,451</td><td>113,628</td><td>76,536</td></tr><tr><td>Reconciliation to cash flow statement:</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Change in long-term receivables</td><td></td><td></td><td></td><td>-52,583</td><td>-61,316</td></tr><tr><td>Provision for doubtful accounts</td><td></td><td></td><td></td><td>6,433</td><td>7,416</td></tr><tr><td>Receivables from acquisition</td><td></td><td></td><td></td><td>-16,420</td><td>—</td></tr><tr><td>Change in receivables in cash flow statement</td><td></td><td></td><td></td><td>$51,058</td><td>$22,636</td></tr></table>
<table><tr><td colspan="2">Completion Factor(a):</td><td colspan="2">Claims Trend Factor(b):</td></tr><tr><td> Factor Change</td><td>Increase (Decrease) in Benefits Payable</td><td> Factor Change</td><td>(Decrease) Increase in Benefits Payable</td></tr><tr><td colspan="4">(dollars in thousands)</td></tr><tr><td>1.50%</td><td>$-172,100</td><td>-10%</td><td>$-399,700</td></tr><tr><td>1.00%</td><td>$-114,700</td><td>-8%</td><td>$-319,700</td></tr><tr><td>0.50%</td><td>$-57,400</td><td>-6%</td><td>$-239,800</td></tr><tr><td>0.25%</td><td>$-28,700</td><td>-4%</td><td>$-159,900</td></tr><tr><td>-0.50%</td><td>$57,400</td><td>-2%</td><td>$-79,900</td></tr><tr><td>-1.00%</td><td>$114,700</td><td>2%</td><td>$79,900</td></tr></table>
<table><tr><td></td><td>Concentra (in thousands)</td></tr><tr><td>Cash and cash equivalents</td><td>$21,317</td></tr><tr><td>Receivables</td><td>108,571</td></tr><tr><td>Other current assets</td><td>20,589</td></tr><tr><td>Property and equipment</td><td>131,837</td></tr><tr><td>Goodwill</td><td>531,372</td></tr><tr><td>Other intangible assets</td><td>188,000</td></tr><tr><td>Other long-term assets</td><td>12,935</td></tr><tr><td>Total assets acquired</td><td>1,014,621</td></tr><tr><td>Current liabilities</td><td>-100,091</td></tr><tr><td>Other long-term liabilities</td><td>-109,811</td></tr><tr><td>Total liabilities assumed</td><td>-209,902</td></tr><tr><td>Net assets acquired</td><td>$804,719</td></tr></table>

Question: In the year with lowest amount of TRICARE subtotal, what's the increasing rate of Commercial and other?
Answer: 0.21579
Reasoning program: subtract(178577,146882), divide(#0,146882)