The following table summarizes the premiums and losses that are ceded by the Company to Mt.
Logan Re segregated accounts and assumed by the Company from Mt.
Logan Re segregated accounts.
## Table 0 ##
Each segregated account is permitted to assume net risk exposures equal to its amount of preferred shares and posted collateral, which in the aggregate was $932,243 thousand and $798,548 thousand at December 31, 2016 and 2015, respectively.
Of this amount, Group had invested $55,536 thousand and $50,000 thousand at December 31, 2016 and 2015, respectively, in the preferred shares.
On April 24, 2014, the Company entered into two collateralized reinsurance agreements with Kilimanjaro Re Limited (“Kilimanjaro”), a Bermuda based special purpose reinsurer, to provide the Company with catastrophe reinsurance coverage.
These agreements are multi-year reinsurance contracts which cover specified named storm and earthquake events.
The first agreement provides up to $250,000 thousand of reinsurance coverage from named storms in specified states of the Southeastern United States.
The second agreement provides up to $200,000 thousand of reinsurance coverage from named storms in specified states of the Southeast, Mid-Atlantic and Northeast regions of the United States and Puerto Rico as well as reinsurance coverage from earthquakes in specified states of the Southeast, Mid-Atlantic, Northeast and West regions of the United States, Puerto Rico and British Columbia.
On November 18, 2014, the Company entered into a collateralized reinsurance agreement with Kilimanjaro Re to provide the Company with catastrophe reinsurance coverage.
This agreement is a multi-year reinsurance contract which covers specified earthquake events.
The agreement provides up to $500,000 thousand of reinsurance coverage from earthquakes in the United States, Puerto Rico and Canada.
On December 1, 2015 the Company entered into two collateralized reinsurance agreements with Kilimanjaro Re to provide the Company with catastrophe reinsurance coverage.
These agreements are multi-year reinsurance contracts which cover named storm and earthquake events.
The first agreement provides up to $300,000 thousand of reinsurance coverage from named storms and earthquakes in the United States, Puerto Rico and Canada.
The second agreement provides up to $325,000 thousand of reinsurance coverage from named storms and earthquakes in the United States, Puerto Rico and Canada.
Kilimanjaro has financed the various property catastrophe reinsurance coverage by issuing catastrophe bonds to unrelated, external investors.
On April 24, 2014, Kilimanjaro issued $450,000 thousand of notes (“Series 2014-1 Notes”).
On November 18, 2014, Kilimanjaro issued $500,000 thousand of notes (“Series 2014-2 Notes”).
On December 1, 2015, Kilimanjaro issued $625,000 thousand of notes (“Series 2015-1 Notes).
The proceeds from the issuance of the Series 2014-1 Notes, the Series 2014-2 Notes and the Series 2015-1 Notes are held in reinsurance trust throughout the duration of the applicable reinsurance agreements and invested solely in US government money market funds with a rating of at least “AAAm” by Standard & Poor’s.
RISKS RELATING TO OUR BUSINESS Fluctuations in the financial markets could result in investment losses.
Prolonged and severe disruptions in the overall public debt and equity markets, such as occurred during 2008, could result in significant realized and unrealized losses in our investment portfolio.
Although financial markets have significantly improved since 2008, they could deteriorate in the future.
There could also be disruption in individual market sectors, such as occurred in the energy sector in recent years.
Such declines in the financial markets could result in significant realized and unrealized losses on investments and could have a material adverse impact on our results of operations, equity, business and insurer financial strength and debt ratings.
Our results could be adversely affected by catastrophic events.
We are exposed to unpredictable catastrophic events, including weather-related and other natural catastrophes, as well as acts of terrorism.
Any material reduction in our operating results caused by the occurrence of one or more catastrophes could inhibit our ability to pay dividends or to meet our interest and principal payment obligations.
By way of illustration, during the past five calendar years, pre-tax catastrophe losses, net of contract specific reinsurance but before cessions under corporate reinsurance programs, were as follows:
## Table 1 ##
Our losses from future catastrophic events could exceed our projections.
We use projections of possible losses from future catastrophic events of varying types and magnitudes as a strategic underwriting tool.
We use these loss projections to estimate our potential catastrophe losses in certain geographic areas and decide on the placement of retrocessional coverage or other actions to limit the extent of potential losses in a given geographic area.
These loss projections are approximations, reliant on a mix of quantitative and qualitative processes, and actual losses may exceed the projections by a material amount, resulting in a material adverse effect on our financial condition and results of operations.
The following discusses the underwriting results for each of our segments for the periods indicated.
U. S.  Reinsurance.
The following table presents the underwriting results and ratios for the U. S.  Reinsurance segment for the periods indicated.
## Table 2 ##
Premiums.
Gross written premiums decreased by 1.0% to $2,125.8 million in 2016 from $2,147.9 million in 2015, primarily due to a decrease in treaty property business, partially offset by an increase in treaty casualty business.
Net written premiums increased by 6.2% to $1,970.6 million in 2016 compared to $1,855.9 million in 2015.
The difference between the change in gross written premiums compared to the change in net written premiums is primarily due to the assumption of the crop business due to the sale of Heartland and a concurrent new crop reinsurance contract.
Premiums earned increased 6.1% to $2,072.2 million in 2016, compared to $1,952.7 million in 2015.
The change in premiums earned relative to net written premiums is primarily the result of timing; premiums are earned ratably over the coverage period whereas written premiums are recorded at the initiation of the coverage period.
Gross written premiums decreased by 0.3% to $2,147.9 million in 2015 from $2,154.5 million in 2014, primarily due to a decrease in treaty casualty business resulting from the cancellation of some contracts.
Net written premiums decreased by 6.4% to $1,855.9 million in 2015 compared to $1,983.8 million in 2014.
The difference between the change in gross written premiums compared to the change in net written premiums was due to a higher utilization of reinsurance.
Premiums earned decreased 1.7% to $1,952.7 million in 2015 compared to $1,986.8 million in 2014.
The change in premiums earned relative to net written premiums is primarily the result of timing; premiums are earned ratably over the coverage period whereas written premiums are recorded at the initiation of the coverage period.

Tables referenced above, in order (Table 0 first):
<table><tr><td></td><td colspan="3">Years Ended December 31,</td></tr><tr><td>Mt. Logan Re Segregated Accounts</td><td>2016</td><td>2015</td><td>2014</td></tr><tr><td>(Dollars in thousands)</td><td></td><td></td><td></td></tr><tr><td>Ceded written premiums</td><td>197,537</td><td>234,001</td><td>138,362</td></tr><tr><td>Ceded earned premiums</td><td>191,568</td><td>226,385</td><td>139,317</td></tr><tr><td>Ceded losses and LAE</td><td>44,802</td><td>40,807</td><td>30,598</td></tr><tr><td>Assumed written premiums</td><td>14,563</td><td>15,421</td><td>13,889</td></tr><tr><td>Assumed earned premiums</td><td>14,563</td><td>15,421</td><td>13,889</td></tr><tr><td>Assumed losses and LAE</td><td>-</td><td>-</td><td>-</td></tr></table>
<table><tr><td>Calendar year:</td><td>Pre-tax catastrophe losses</td></tr><tr><td>(Dollars in millions)</td><td></td></tr><tr><td>2016</td><td>$301.2</td></tr><tr><td>2015</td><td>53.8</td></tr><tr><td>2014</td><td>56.3</td></tr><tr><td>2013</td><td>194.0</td></tr><tr><td>2012</td><td>410.0</td></tr></table>
<table><tr><td></td><td colspan="3">Years Ended December 31,</td><td colspan="2">2016/2015</td><td colspan="2">2015/2014</td></tr><tr><td>(Dollars in millions)</td><td>2016</td><td>2015</td><td>2014</td><td>Variance</td><td>% Change</td><td>Variance</td><td>% Change</td></tr><tr><td>Gross written premiums</td><td>$2,125.8</td><td>$2,147.9</td><td>$2,154.5</td><td>$-22.1</td><td>-1.0%</td><td>$-6.6</td><td>-0.3%</td></tr><tr><td>Net written premiums</td><td>1,970.6</td><td>1,855.9</td><td>1,983.8</td><td>114.7</td><td>6.2%</td><td>-127.9</td><td>-6.4%</td></tr><tr><td>Premiums earned</td><td>$2,072.2</td><td>$1,952.7</td><td>$1,986.8</td><td>$119.5</td><td>6.1%</td><td>$-34.1</td><td>-1.7%</td></tr><tr><td>Incurred losses and LAE</td><td>1,068.5</td><td>825.1</td><td>954.5</td><td>243.4</td><td>29.5%</td><td>-129.4</td><td>-13.6%</td></tr><tr><td>Commission and brokerage</td><td>466.0</td><td>493.3</td><td>466.3</td><td>-27.3</td><td>-5.5%</td><td>27.0</td><td>5.8%</td></tr><tr><td>Other underwriting expenses</td><td>54.1</td><td>50.1</td><td>45.6</td><td>4.0</td><td>8.0%</td><td>4.5</td><td>9.9%</td></tr><tr><td>Underwriting gain (loss)</td><td>$483.6</td><td>$584.3</td><td>$520.4</td><td>$-100.6</td><td>-17.2%</td><td>$63.9</td><td>12.3%</td></tr><tr><td></td><td></td><td></td><td></td><td></td><td>Point Chg</td><td></td><td>Point Chg</td></tr><tr><td>Loss ratio</td><td>51.6%</td><td>42.3%</td><td>48.0%</td><td></td><td>9.3</td><td></td><td>-5.7</td></tr><tr><td>Commission and brokerage ratio</td><td>22.5%</td><td>25.3%</td><td>23.5%</td><td></td><td>-2.8</td><td></td><td>1.8</td></tr><tr><td>Other underwriting expense ratio</td><td>2.6%</td><td>2.5%</td><td>2.3%</td><td></td><td>0.1</td><td></td><td>0.2</td></tr><tr><td>Combined ratio</td><td>76.7%</td><td>70.1%</td><td>73.8%</td><td></td><td>6.6</td><td></td><td>-3.7</td></tr><tr><td>(NM, not meaningful)</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>(Some amounts may not reconcile due to rounding.)</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr></table>

Question: what's the total amount of Gross written premiums of Years Ended December 31, 2014, and Assumed written premiums of Years Ended December 31, 2015 ?
Answer: 17575.5
Reasoning program: add(2154.5,15421.0)