The growth potential of the RFID industry can be summed up by Wall Street’s reaction to the Impinj initial public offering over the last six weeks. Impinj blew by analyst expectations when it announced its second quarter results on Aug. 31, rising nearly 21 percent to close at $27.57 a share. Impinj, which priced its IPO at $14 on July 21, saw its stock jump 28% on its first day of trading, closing a few cents shy of $18.

Impinj, which went public on July 21, saw its stock climb 20 percent on Sept. 1 after Q2 results exceeded expectations.

Impinj expects to sell more RFID tags this year than previously reported, raising estimates from 4.3-4.5 billion to 4.9-5.1 billion units. The company said that Q2 revenue grew 36% year-over-year to $26.0 million, and projected third quarter sales of $27.4 million to $28.9 million. Non-GAAP net income of $0.9 million, or $0.06 per share, was higher than industry analyst projections.

“We see a massive and growing market opportunity for our offerings and, with the successful completion of our IPO, we have expanded our available capital and will continue to execute our strategy to further capitalize on this exciting growth opportunity,” says Chris Diorio, Impinj co-founder and CEO. “Revenue grew 36% year-over-year to a record driven by continued demand for our Monza endpoint ICs, which we believe is an indication of accelerating market growth and our strong market position.”

Impinj has rallied around strong retail growth in apparel RFID tagging. Major retail chains like Macy’s are tagging most clothing items to increase inventory visibility and enable omni-channel shopping.

In a research report, Needham analyst James Ricchiuti made bullish comments about Impinj, saying that it is seeing strong growth in retail and healthcare markets, as well as industrial and commercial markets such as baggage handling. Delta recently announced that it will tag 120 million luggage items a year.

RBC Capital Markets told Investor’s Business Daily that total spending on IoT endpoint hardware was about $1.2 trillion in 2015, and is expected to grow to about $3 trillion in 2020. RBC estimates that the RFID market was about $10 billion in 2015 or approximately 0.85% of total IoT spending. By applying the same ratio, RBC estimates that the market could grow to over $20 billion by 2020.