From the WSGR Database: Financing Trends for 2017 -

The strong venture financing market of 2017 continued in Q4, resulting in a record-breaking year for median valuations and amounts raised in Series B and later financings. Median pre-money valuations for full-year 2017 Series B financings exceeded those of the past five years. Series C and later median pre-money valuations also reached an all-time high of $179.8 million in full-year 2017—twice the median pre-money valuation reported in full-year 2016. Strong pre-money valuations accompanied high median amounts raised across all rounds of financing in full-year 2017, topping the prior five years. High pre-money valuations also boosted the percentage of up rounds to 85% of all Series B and later financings for full-year 2017.