The SPDR S&P 500 ETF (NYSEArca: SPY), the first U.S.-listed ETF and currently the biggest, with more than $125 billion in assets, gapped higher Thursday and rallied above what stands as its highest-ever closing level, as its underlying benchmark, the S&P 500, flirted with all-time highs.

SPY traded as high as $156.59 a share shortly after the opening bell, breaking through $156.48—what was its highest closing on record, reached on Oct. 9, 2007, until Thursday. Indeed, gains of 0.5 percent pushed the fund to settle at $156.73 while its underlying benchmark, too, rallied to close at 1,563.23—Oct. 9, 2007, still stands as the day when the S&P 500 posted its highest-ever closing of 1,565.15.

Thursday, the broad U.S. stock index underpinning the ETF was working toward extending what’s now a 10-day winning streak for U.S. stocks that has been fueled by the growing perception that the economy is recovering.

The latest round of economic data released Thursday included a decline in unemployment benefit filings in the most recent week—marking the third-consecutive week of improvement—at a time when producer prices were also reported to be on the rise.

Strength in the U.S. dollar remained another underlying factor supporting the rally, encouraging U.S. investors to pour assets into the U.S. equities markets.

SPY has attracted nearly $7 billion in fresh assets in the past 10 trading days, while U.S. equities ETFs, as a group, saw fresh net inflows of nearly $5 billion in the week ended March 7, following inflows of $1.75 billion the week before, according to data compiled by IndexUniverse.

While talks of a corrective retreat are starting to gather steam among analysts and economists, the S&P 500 was up another 8 points Thursday, having gained more than 3.2 percent in the past 10 days.

The highest trading level for the S&P 500 remains an intraday high of 1,576.09 reached on Oct. 11, 2007, when SPY reached a high of $157.52 a share.

A few other interesting data points about the S&P 500, all provided by S&P Dow Jones Indices, include:

• The full market value of the S&P 500 issues as of March 13, 2013 was $14.72 trillion.
• Exxon Mobil is the benchmark’s top holding, with a market value of $407.0 billion.
• The worst year for the S&P 500 was 2008, when the index posted a 38.49 percent decline.
• The largest single-day percentage gain for the S&P 500 was 11.58 percent, seen on Oct. 13, 2008. That also represented the largest single-day point increase: 104.13 points.
• The largest single-day point decline was 106.85 points, or 8.81 percent, seen on Sept. 29, 2008.