As described in Note 1 on Summary of Significant Accounting Policies – New Accounting Pronouncements Recently Adopted, we adopted Topic 842 as of January 1, 2019. Prior period amounts have not been adjusted and continue to be reported in accordance with historical accounting under Topic 840.

We have an operating lease for our office space at 149 Commonwealth Drive, Menlo Park, California, that commenced in February 2018 and expires in January 2020. We have an option to extend the lease for one additional period of two years, which we did not include in determining the right-of-use asset or lease liability as we did not consider it reasonably certain that we would exercise such option. Since the operating lease is a net lease, as the non-lease components (i.e., common area maintenance) are paid separately from rent based on actual costs incurred, such non-lease components were not included in the right-of-use asset and liability and are reflected as an expense in the period incurred.

The components of lease costs included in operating expenses in our condensed statements of operations were as follows:

	Three Months Ended March 31,
(In thousands)	2019		2018
Operating lease costs	$	173	$	168
Variable lease costs⁽¹⁾		2		24
Total lease costs	$	175	$	192

(1)

Variable lease costs represent non-lease components, such as common area maintenance charges.

The operating lease liability on the condensed balance sheet reflects the present value of the remaining lease payments over the remaining lease term. In determining the present value of lease payments, we applied our incremental borrowing rate based on the information available as of the January 1, 2019 adoption date. As of March 31, 2019, future minimum payments under the operating lease were as follows (in thousands):

2019	$	525
2020		58
Total lease payments		583
Less: imputed interest		(12	)
Total	$	571

As of March 31, 2019, the weighted average remaining lease term is 10 months and the weighted average discount rate used to determine the operating lease liability was 5%.

We have performed an evaluation of our other contracts with vendors in accordance with Topic 842 and have determined that, except for the operating lease described above and a nominal financing lease for office equipment, none of our contracts contain a lease.