Fireworks soar over the Olympic Stadium during the Closing Ceremony at the 2012 Summer Olympics, Monday, Aug. 13, 2012, in London. (AP Photo/David J. Phillip)

The Spice Girls perform during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Kristy Wigglesworth)

The Olympic Stadium is shown during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/David J. Phillip)

George Michael performs during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Kristy Wigglesworth)

Athletes arrive during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Martin Meissner)

Artists perform during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Sergei Grits)

Artists perform during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Martin Meissner)

One Direction perform during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Charlie Riedel)

Acrobats perform on stage during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Matt Dunham)

Fireworks explode during the Closing Ceremony at the 2012 Summer Olympics, Monday, Aug. 13, 2012, in London. (AP Photo/Alastair Grant)

Fireworks explode during the Closing Ceremony at the 2012 Summer Olympics, Monday, Aug. 13, 2012, in London. (AP Photo/Martin Meissner)

Fireworks go off during the closing ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Andrew Medichini)

Fireworks go off during the closing ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Andrew Medichini)

The Olympic flame burns during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Julio Cortez)

The Spice Girls perform during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Kristy Wigglesworth)

The Spice Girls perform during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Hassan Ammar)

Russell Brand performs "I am the Walrus," during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Hassan Ammar)

Jessie J performs during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Kristy Wigglesworth)

One Direction perform during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Kristy Wigglesworth)

Britain's Prince Harry applauds during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Charlie Riedel)

An artist performs during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Charlie Riedel)

Artists perform during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Martin Meissner)

Performers cheer during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Jae C. Hong)

Jesse J performs during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Martin Meissner)

Jesse J performs during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Morry Gash)

Jessie J performs during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Charlie Riedel)

Brian May performs during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Charlie Riedel)

An artist performs during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Charlie Riedel)

Liam Gallagher performs during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Matt Dunham)

Ethiopian athletes attend the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Dmitry Lovetsky)

Performers cycle on the stage during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Jae C. Hong)

French athletes parade during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Matt Dunham)

Athletes enter the arena during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Matt Slocum)

George Michael performs during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Charlie Riedel)

Annie Lennox performs during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Charlie Riedel)

Fatboy Slim performs during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Kristy Wigglesworth)

The Spice Girls perform during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Charlie Riedel)

Catherine, Duchess of Cambridge, watches the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Charlie Riedel)

A performer waves a British flag during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Kristy Wigglesworth)

A performer stands atop a cannon during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Jae C. Hong)

The Rio 2016 logo is paraded during the Closing Ceremony at the 2012 Summer Olympics, Sunday, Aug. 12, 2012, in London. (AP Photo/Matt Slocum)