Total stockholders' equity increased 38.4% from $187.7 million at December 31, 2018, to $259.8 million at December 31, 2019 primarily due to a change in net unrealized gains on available-for-sale securities after taxes of $71.8 million in 2019 as market interest rates decreased from 2018 levels.
Insurance premiums declined 1.9% in 2019 compared to 2018, totaling $184.3 million and $187.9 million, respectively. The decline was driven by fewer renewal premiums in our Life Insurance segment, partially offset by an increase in first year premiums in that segment as we realized growth in 2019 following investment in our sales and marketing activities and increased sales of higher average premium policies. First year premiums in our Life Insurance segment increased 2.1% in 2019 compared
Amortization of DAC. Amortization of DAC totaled $28.3 million, $34.2 million and $29.7 million in 2019, 2018 and 2017, respectively. Year over year changes resulted primarily from the new actuarial system conversion increasing amortization by $3.7 million in 2018 and higher surrender activity, including early duration elections to convert existing policies to reduced paid up ("RPU") or extended term insurance ("ETI") status in 2019 and 2018. There is higher DAC associated with early duration conversions to RPU or ETI, which increases amortization expense. Amortization of DAC is also impacted by persistency and the level of surrenders.
Sales from Colombia, Venezuela and Taiwan represented the majority of the new business premiums in 2019, 2018 and 2017. Overall, three of our top five countries listed above experienced a decline in premium levels from 2018 to 2019, with Venezuela leading the decline. While overall premiums declined in 2019 compared to 2018 due to a decrease in renewal premiums, first year premiums increased during the period. Our international business and premiums could be impacted by our inability to comply with current or future foreign laws or regulations applicable to the Company or our independent consultants in the countries where we accept applications. In addition, marketing or operational changes made by the Company to comply with those laws or regulations may adversely impact our
This operating unit represents the administrative support entities to the insurance operations whose revenues are primarily intercompany and have been eliminated in consolidation under U.S. GAAP, which typically results in a segment loss. Losses reported for 2019 were impacted by the impairment of the Citizens Academy training facility property. In 2018, higher expenses included long-term compensation and increased audit fees as discussed in the segment analysis.
(2) Includes $130.1 million and $108.5 million of U.S. Government agencies and government-sponsored enterprises for the years ended December 31, 2019 and 2018, respectively.
The table below represents the Company’s detailed exposure to municipal holdings in Texas, which comprises the most significant state concentration of the total municipal fixed maturity portfolio as of December 31, 2019.
Cash flows from our insurance operations historically have been sufficient to meet current needs. Cash flows from operating activities were $72.2 million, $84.6 million and $93.0 million for the years ended December 31, 2019, 2018 and 2017, respectively. Operating cash flow declined in 2019, due primarily to the decrease in premium revenues and higher policyholder benefits paid in 2019. We have traditionally also had significant cash flows from both scheduled and unscheduled fixed maturity security calls, maturities, redemptions, and prepayments, which totaled $181.6 million, $86.6 million and $84.0 million in 2019, 2018 and 2017, respectively. These cash flows, for the most part, are reinvested in fixed maturity securities. Net cash outflows from investment activity totaled $69.3 million, $85.1 million and $85.0 million for the years ended December 31, 2019, 2018 and 2017, respectively. The outflows from investing activities for the year ended December 31, 2019, were primarily related to the investment of excess cash and cash equivalents generated from operations during 2019 and 2018. The Company's cash outflows from financing activities were $2.2 million, $0.1 million and cash inflows of $2.5 million in 2019, 2018 and 2017, respectively.
See Parent Company Liquidity and Capital Resources below for a discussion of additional Parent Company liquidity.
DAC is subject to recoverability testing at the time of policy issuance and loss recognition testing on an annual basis, or when an event occurs that might require loss recognition testing. If loss recognition or impairment is necessary, DAC would be written off to the extent that anticipated future premiums and investment income is insufficient to cover expected future policy benefits and expenses. Loss recognition testing considers, among other things, actual experience and projected future experience and calculates the available premium (gross premium less the benefit and expense portion of premium) for the next 50 years. DAC is evaluated for recoverability using best estimate assumptions. Based on the results of DAC recoverability testing and loss recognition testing, management believes that our DAC and related amortization for the years ended December 31, 2019, 2018 and 2017 limits the amount of deferred costs to its estimated realizable value.