Markets are likely to be in for a bumpy ride after April 2007.

The claim gives no date, so judge it over the following roughly 20 months (through end-2008). True: major equity markets had marked volatility and turbulence after April 2007, for example a peak-to-trough decline of 10% or more in the S&P 500 or global equities, or VIX readings well above its 2006–early-2007 levels. Mostly true: there was noticeable turbulence, but it was modest or short-lived (corrections of about 5–10%). Mostly false: markets were mostly calm, with only minor wobbles. False: markets rose smoothly with low volatility throughout the period.

Set before the research began.

1. E1 Overview: credit retrenchment triggers liquidity squeeze Bank for International Settlements (BIS Quarterly Review, September 2007) · September 2007

   “steadily in July and August, reaching an intraday peak of 37.5% on 16 August”

2. E2 Box A: Volatility in Global Financial Markets Reserve Bank of Australia (Statement on Monetary Policy, February 2009) · February 2009

   “However, volatility increased sharply to historically high levels following”

3. E3 [PDF] VI. Financial markets - BIS 78th Annual Report - June 2008 Bank for International Settlements (78th Annual Report) · June 2008

   “with the broad MSCI emerging market index down 18% by 17 August, compared to a 10% decline in the global index over the same period.”

4. E4 S&P 500 Historical Prices by Month multpl.com (citing Standard & Poor's and Robert Shiller)

   “| Oct 1, 2007 | 1,539.66 |”

The BIS 78th Annual Report (E3) says the global equity index fell 10% and the MSCI emerging market index fell 18% by 17 August, which falls within the window after April 2007. That meets the criteria's threshold of a 10% or larger peak-to-trough drop in global equities. The RBA's February 2009 box on global market volatility (E2) adds that volatility rose sharply to historically high levels. The figure in E1 and the single S&P 500 row in E4 don't say enough on their own about what they measure, so they are only background.