December 31,
(In thousands)
2019
2018
Software development costs
$428,641
$317,637
Less: accumulated amortization
(184,712)
(107,977)
Software development costs, net
$243,929
$209,660

text: Software Development Costs
text: We capitalize purchased software upon acquisition if it is accounted for as internal-use software or if it meets the future alternative use criteria. We capitalize incurred labor costs for software development from the time technological feasibility of the software is established, or when the preliminary project phase is completed in the case of internal-use software, until the software is available for general release. Research and development costs and other computer software maintenance costs related to software development are expensed as incurred.
text: We estimate the useful life of our capitalized software and amortize its value over that estimated life. If the actual useful life is shorter than our estimated useful life, we will amortize the remaining book value over the remaining useful life or the asset may be deemed to be impaired and, accordingly, a write-down of the value of the asset may be recorded as a charge to earnings.
text: Upon the availability for general release, we commence amortization of the capitalized software costs on a product by product basis. Amortization of capitalized software is recorded using the greater of (i) the ratio of current revenues to total and anticipated future revenues for the applicable product or (ii) the straightline method over the remaining estimated economic life, which is estimated to be three to five years.
text: At each balance sheet date, the unamortized capitalized costs of a software product are compared with the net realizable value of that product. The net realizable value is the estimated future gross revenues from that product reduced by the estimated future costs of completing and disposing of that product, including the costs of performing maintenance and client support required to satisfy our responsibility set forth at the time of sale.
text: The amount by which the unamortized capitalized costs of a software product exceed the net realizable value of that asset is written off. If we determine that the value of the capitalized software could not be recovered, a write-down of the value of the capitalized software to its recoverable value is recorded as a charge to earnings. The unamortized balances of capitalized software were as follows:

Questions:
question: When is the purchased software capitalized?
answer: upon acquisition if it is accounted for as internal-use software or if it meets the future alternative use criteria
question: How is the amortization of capitalized software recorded?
answer: using the greater of (i) the ratio of current revenues to total and anticipated future revenues for the applicable product or (ii) the straightline method over the remaining estimated economic life, which is estimated to be three to five years.
question: What is the Software development costs in 2019?
answer: $428,641
scale: thousand
question: What is the change in the Software development costs from 2018 to 2019?
answer: 111004
derivation: 428,641 - 317,637
scale: thousand
question: What is the average accumulated amortization for 2018 and 2019?
answer: -146344.5
derivation: -(184,712 + 107,977) / 2
scale: thousand
question: What is the percentage change in Software development costs, net from 2018 to 2019?
answer: 0.16
derivation: 243,929 / 209,660 - 1
scale: percent