table of contents ( 4 ) the decline in cash flows was driven by the timing of inventory purchases at the end of 2014 versus 2013 . in order to manage our working capital and operating cash needs , we monitor our cash conversion cycle , defined as days of sales outstanding in accounts receivable plus days of supply in inventory minus days of purchases outstanding in accounts payable , based on a rolling three-month average . components of our cash conversion cycle are as follows: .

Table:
( in days ) | december 31 , 2015 | december 31 , 2014 | december 31 , 2013
days of sales outstanding ( dso ) ( 1 ) | 48 | 42 | 44
days of supply in inventory ( dio ) ( 2 ) | 13 | 13 | 14
days of purchases outstanding ( dpo ) ( 3 ) | -40 ( 40 ) | -34 ( 34 ) | -35 ( 35 )
cash conversion cycle | 21 | 21 | 23
( 1 ) represents the rolling three-month average of the balance of trade accounts receivable , net at the end of the period divided by average daily net sales for the same three-month period .
also incorporates components of other miscellaneous receivables .
( 2 ) represents the rolling three-month average of the balance of merchandise inventory at the end of the period divided by average daily cost of goods sold for the same three-month period .
( 3 ) represents the rolling three-month average of the combined balance of accounts payable-trade , excluding cash overdrafts , and accounts payable-inventory financing at the end of the period divided by average daily cost of goods sold for the same three-month period .
the cash conversion cycle remained at 21 days at december 31 , 2015 and december 31 , 2014 .
the increase in dso was primarily driven by a higher accounts receivable balance at december 31 , 2015 driven by higher public segment sales where customers generally take longer to pay than customers in our corporate segment , slower government payments in certain states due to budget issues and an increase in net sales and related accounts receivable for third-party services such as software assurance and warranties .
these services have an unfavorable impact on dso as the receivable is recognized on the balance sheet on a gross basis while the corresponding sales amount in the statement of operations is recorded on a net basis .
these services have a favorable impact on dpo as the payable is recognized on the balance sheet without a corresponding cost of sale in the statement of operations because the cost paid to the vendor or third-party service provider is recorded as a reduction to net sales .
in addition to the impact of these services on dpo , dpo also increased due to the mix of payables with certain vendors that have longer payment terms .
the cash conversion cycle decreased to 21 days at december 31 , 2014 compared to 23 days at december 31 , 2013 , primarily driven by improvement in dso .
the decline in dso was primarily driven by improved collections and early payments from certain customers .
additionally , the timing of inventory receipts at the end of 2014 had a favorable impact on dio and an unfavorable impact on dpo .
investing activities net cash used in investing activities increased $ 189.6 million in 2015 compared to 2014 .
the increase was primarily due to the completion of the acquisition of kelway by purchasing the remaining 65% ( 65 % ) of its outstanding common stock on august 1 , 2015 .
additionally , capital expenditures increased $ 35.1 million to $ 90.1 million from $ 55.0 million for 2015 and 2014 , respectively , primarily for our new office location and an increase in spending related to improvements to our information technology systems .
net cash used in investing activities increased $ 117.7 million in 2014 compared to 2013 .
we paid $ 86.8 million in the fourth quarter of 2014 to acquire a 35% ( 35 % ) non-controlling interest in kelway .
additionally , capital expenditures increased $ 7.9 million to $ 55.0 million from $ 47.1 million in 2014 and 2013 , respectively , primarily for improvements to our information technology systems during both years .
financing activities net cash used in financing activities increased $ 114.5 million in 2015 compared to 2014 .
the increase was primarily driven by share repurchases during the year ended december 31 , 2015 which resulted in an increase in cash used for financing activities of $ 241.3 million .
for more information on our share repurchase program , see item 5 , 201cmarket for registrant 2019s common equity , related stockholder matters and issuer purchases of equity securities . 201d the increase was partially offset by the changes in accounts payable-inventory financing , which resulted in an increase in cash provided for financing activities of $ 20.4 million , and the net impact of our debt transactions which resulted in cash outflows of $ 7.1 million and $ 145.9 million during the years .

Question: from dec 31 , 2013 to dec 31 , 2014 , what was the percentage decrease in the length of the cash conversion cycle?
Answer: 9.5%
Calculation: subtract(23, 21), divide(#0, 21), multiply(#1, const_100)