the following table sets forth information concerning increases in the total number of our aap stores during the past five years : beginning stores new stores ( 1 ) stores closed ending stores ( 1 ) does not include stores that opened as relocations of previously existing stores within the same general market area or substantial renovations of stores . our store-based information systems , which are designed to improve the efficiency of our operations and enhance customer service , are comprised of a proprietary pos system and electronic parts catalog , or epc , system . information maintained by our pos system is used to formulate pricing , marketing and merchandising strategies and to replenish inventory accurately and rapidly . our pos system is fully integrated with our epc system and enables our store team members to assist our customers in their parts selection and ordering based on the year , make , model and engine type of their vehicles . our centrally-based epc data management system enables us to reduce the time needed to ( i ) exchange data with our vendors and ( ii ) catalog and deliver updated , accurate parts information . our epc system also contains enhanced search engines and user-friendly navigation tools that enhance our team members' ability to look up any needed parts as well as additional products the customer needs to complete an automotive repair project . if a hard-to-find part or accessory is not available at one of our stores , the epc system can determine whether the part is carried and in-stock through our hub or pdq ae networks or can be ordered directly from one of our vendors . available parts and accessories are then ordered electronically from another store , hub , pdq ae or directly from the vendor with immediate confirmation of price , availability and estimated delivery time . we also support our store operations with additional proprietary systems and customer driven labor scheduling capabilities . our store-level inventory management system provides real-time inventory tracking at the store level . with the store-level system , store team members can check the quantity of on-hand inventory for any sku , adjust stock levels for select items for store specific events , automatically process returns and defective merchandise , designate skus for cycle counts and track merchandise transfers . our stores use radio frequency hand-held devices to help ensure the accuracy of our inventory . our standard operating procedure , or sop , system is a web-based , electronic data management system that provides our team members with instant access to any of our standard operating procedures through a comprehensive on-line search function . all of these systems are tightly integrated and provide real-time , comprehensive information to store personnel , resulting in improved customer service levels , team member productivity and in-stock availability . purchasing for virtually all of the merchandise for our stores is handled by our merchandise teams located in three primary locations : 2022 store support center in roanoke , virginia ; 2022 regional office in minneapolis , minnesota ; and 2022 global sourcing office in taipei , taiwan . our roanoke team is primarily responsible for the parts categories and our minnesota team is primarily responsible for accessories , oil and chemicals . our global sourcing team works closely with both teams . in fiscal 2011 , we purchased merchandise from approximately 500 vendors , with no single vendor accounting for more than 9% ( 9 % ) of purchases . our purchasing strategy involves negotiating agreements with most of our vendors to purchase merchandise over a specified period of time along with other terms , including pricing , payment terms and volume . the merchandising team has developed strong vendor relationships in the industry and , in a collaborative effort with our vendor partners , utilizes a category management process where we manage the mix of our product offerings to meet customer demand . we believe this process , which develops a customer-focused business plan for each merchandise category , and our global sourcing operation are critical to improving comparable store sales , gross margin and inventory productivity. .

Table: 2011 2010 2009 2008 2007 beginning stores 3369 3264 3243 3153 2995 new stores ( 1 ) 95 110 75 109 175 stores closed -4 ( 4 ) -5 ( 5 ) -54 ( 54 ) -19 ( 19 ) -17 ( 17 ) ending stores 3460 3369 3264 3243 3153

the following table sets forth information concerning increases in the total number of our aap stores during the past five years : beginning stores new stores ( 1 ) stores closed ending stores ( 1 ) does not include stores that opened as relocations of previously existing stores within the same general market area or substantial renovations of stores . our store-based information systems , which are designed to improve the efficiency of our operations and enhance customer service , are comprised of a proprietary pos system and electronic parts catalog , or epc , system . information maintained by our pos system is used to formulate pricing , marketing and merchandising strategies and to replenish inventory accurately and rapidly . our pos system is fully integrated with our epc system and enables our store team members to assist our customers in their parts selection and ordering based on the year , make , model and engine type of their vehicles . our centrally-based epc data management system enables us to reduce the time needed to ( i ) exchange data with our vendors and ( ii ) catalog and deliver updated , accurate parts information . our epc system also contains enhanced search engines and user-friendly navigation tools that enhance our team members' ability to look up any needed parts as well as additional products the customer needs to complete an automotive repair project . if a hard-to-find part or accessory is not available at one of our stores , the epc system can determine whether the part is carried and in-stock through our hub or pdq ae networks or can be ordered directly from one of our vendors . available parts and accessories are then ordered electronically from another store , hub , pdq ae or directly from the vendor with immediate confirmation of price , availability and estimated delivery time . we also support our store operations with additional proprietary systems and customer driven labor scheduling capabilities . our store-level inventory management system provides real-time inventory tracking at the store level . with the store-level system , store team members can check the quantity of on-hand inventory for any sku , adjust stock levels for select items for store specific events , automatically process returns and defective merchandise , designate skus for cycle counts and track merchandise transfers . our stores use radio frequency hand-held devices to help ensure the accuracy of our inventory . our standard operating procedure , or sop , system is a web-based , electronic data management system that provides our team members with instant access to any of our standard operating procedures through a comprehensive on-line search function . all of these systems are tightly integrated and provide real-time , comprehensive information to store personnel , resulting in improved customer service levels , team member productivity and in-stock availability . purchasing for virtually all of the merchandise for our stores is handled by our merchandise teams located in three primary locations : 2022 store support center in roanoke , virginia ; 2022 regional office in minneapolis , minnesota ; and 2022 global sourcing office in taipei , taiwan . our roanoke team is primarily responsible for the parts categories and our minnesota team is primarily responsible for accessories , oil and chemicals . our global sourcing team works closely with both teams . in fiscal 2011 , we purchased merchandise from approximately 500 vendors , with no single vendor accounting for more than 9% ( 9 % ) of purchases . our purchasing strategy involves negotiating agreements with most of our vendors to purchase merchandise over a specified period of time along with other terms , including pricing , payment terms and volume . the merchandising team has developed strong vendor relationships in the industry and , in a collaborative effort with our vendor partners , utilizes a category management process where we manage the mix of our product offerings to meet customer demand . we believe this process , which develops a customer-focused business plan for each merchandise category , and our global sourcing operation are critical to improving comparable store sales , gross margin and inventory productivity. .

Question: what was the average annual store closure from 2007 to 2011?
Answer: 19.8 stores per year
Calculation: divide(add(17, 4), const_2)
Explanation: to find the average amount of closure of stores , one must add all of the closed stores for the years and divide by the amount of years .