First quarter revenues increased 16% year-over-year to $536 million compared to our guidance range of $490 million to $505 million.
Organic growth is a key priority and revenues increased 8% year-over-year on an organic basis.
Incoming order rates were solid during the quarter, increasing 24% year-over-year and 11% sequentially.
This resulted in a healthy book-to-bill ratio of 1.3 times.
EBITDA increased 32% year-over-year to $80 million.
EBITDA margins expanded 180 basis points from 13.1% in the year ago period to 14.9%.
EPS increased 40% year-over-year to $0.94 compared to our guidance range of $0.60 to $0.70.
For the full year 2021, we are increasing the high-end of our revenue and earnings per share guidance ranges by $130 million and $0.50 respectively, largely due to strength in the Industrial Automation and broadband and 5G markets.
As you know, we initiated a process last year to divest approximately $200 million in revenues associated with certain undifferentiated copper cable product lines.
We have plans to open other CICs around the world over the next 12 months to 18 months.
Revenues were $536 million in the quarter, increasing $73 million or 16% from $464 million in the first quarter of 2020.
Revenues were favorably impacted by $33 million from currency translation and higher copper prices and $4 million from acquisitions.
After adjusting for these factors, revenues increased 8% organically from the prior year period.
Incoming order rates were solid during the quarter, increasing 24% year-over-year and 11% sequentially and accelerating as the quarter progressed.
This resulted in a healthy book-to-bill ratio of 1.3 times, with particular strength in Industrial Automation and Broadband and 5G.
Gross profit margins in the quarter were 36%, decreasing 90 basis points compared to 36.9% in the year ago period.
In the first quarter, the pass-through of higher copper prices had an unfavorable impact of approximately 180 basis points.
Excluding this impact, gross profit margins would have increased 90 basis points year-over-year that.
EBITDA was $80 million, increasing $19 million or 32% compared to $61 million in the prior year period.
EBITDA margins were 14.9% compared to 13.1% in the prior year period, an improvement of 180 basis points year-over-year.
The pass-through of higher copper prices had an unfavorable impact of approximately 70 basis points in the quarter.
Excluding this impact, EBITDA margins would have increased 250 basis points year-over-year, demonstrating solid operating leverage on higher volumes.
Net interest expense increased $2 million year-over-year to $16 million as the result of foreign currency translation.
At current foreign exchange rates, we expect interest expense to be approximately $61 million in 2021.
Our effective tax rate was 19.9% in the first quarter, consistent with our expectations.
For financial modeling purposes, we recommend using an effective tax rate of 20% throughout 2021.
Net income in the quarter was $42 million compared to $31 million in the prior year period.
And earnings per share was $0.94, increasing 40% compared to $0.67 in the first quarter of 2020.
The Industrial Solutions segment generated revenues of $310 million in the quarter, increasing 23% from $251 million in the first quarter of 2020.
Currency translation and higher copper prices had a favorable impact of $20 million year-over-year.
And acquisitions had a favorable impact of $4 million.
After adjusting for these factors, revenues increased 14% organically.
Within this segment, Industrial Automation revenues also increased 14% year-over-year on an organic basis, with growth in each of our primary market verticals.
Cybersecurity revenues increased 8% year-over-year in the first quarter, with nonrenewal bookings our best leading indicator of revenues increasing 74%.
Industrial Solutions segment EBITDA margins were 16.6% in the quarter, increasing 250 basis points compared to 14.1% in the year ago period.
The Enterprise Solutions segment generated revenues of $226 million during the quarter, increasing 7% from $212 million in the first quarter of 2020.
Currency translation and higher copper prices had a favorable impact of $13 million year-over-year.
After adjusting for these factors, revenues increased 1% organically.
Revenues in Broadband and 5G increased 9% year-over-year on an organic basis.
This supports continued robust growth in our fiberoptic products, which increased 23% organically in the first quarter.
Revenues in the Smart Buildings market declined 6% year-over-year on an organic basis consistent with our expectation.
Enterprise Solutions segment's EBITDA margins were 12.4% in the quarter, increasing 80 basis points compared to 11.6% in the prior year period.
Our cash and cash equivalents balance at the end of the first quarter was $371 million compared to $502 million in the prior quarter and $251 million in the prior year period.
Working capital turns were 6.7 compared to 10.3 in the prior quarter and 5.6 in the prior year period.
Days sales outstanding of 54 days compared to 50 in the prior quarter and 57 in the prior year period.
Inventory turns were 5.0 compared to 5.2 in the prior quarter and 4.6 in the prior year.
Our debt principal at the end of the first quarter was $1.53 billion compared to $1.59 billion in the prior quarter.
Net leverage was 4 times net debt to EBITDA at the end of the quarter.
This is temporarily above our targeted range of 2 to 3 times, and we expect to trend back to the targeted range as conditions normalize.
As a reminder, our debt is entirely fixed at an attractive average interest rate of 3.5%, with no maturities until 2025 to 2028, and we have no maintenance covenants on this debt.
Cash flow from operations in the first quarter was a use of $42 million compared to a use of $52 million in the prior year period.
Net capital expenditures were $11 million for the quarter compared to $19 million in the prior year period.
And finally, free cash flow in the quarter with a use of $53 million compared to a use of $71 million in the prior year period.
We anticipate second quarter 2021 revenues of $535 million to $550 million and earnings per share of $0.88 to $0.98.
For the full year 2021, we now expect revenues of $2.13 billion to $2.18 billion compared to prior guidance of $1.99 billion to $2.05 billion.
We now expect full year 2021 earnings per share to be $3.50 to $3.80 compared to prior guidance of $2.90 to $3.30.
We expect interest expense of approximately $61 million for 2021 and an effective tax rate of 20% for each quarter and the full year.
This guidance continues to include the contribution of the copper cable product lines that we are in the process of divesting, which contributed approximately $200 million in revenue and $0.20 in earnings per share in 2020.
As a result, we are increasing our volume outlook for the year by $90 million.
Our revised full year guidance implies consolidated organic growth in the range of 6% to 9% compared to our prior expectation of approximately 1% to 4%.
Relative to our prior guidance, we expect higher copper prices and current foreign exchange rate to have a favorable impact on revenues of approximately $40 million in 2021, but a negligible impact on earnings.
For the full year 2021, the high-end of our guidance implies total revenue and earnings per share growth of 17% and 38%, respectively.

Summary:
EPS increased 40% year-over-year to $0.94 compared to our guidance range of $0.60 to $0.70.
And earnings per share was $0.94, increasing 40% compared to $0.67 in the first quarter of 2020.
We anticipate second quarter 2021 revenues of $535 million to $550 million and earnings per share of $0.88 to $0.98.
For the full year 2021, we now expect revenues of $2.13 billion to $2.18 billion compared to prior guidance of $1.99 billion to $2.05 billion.
We now expect full year 2021 earnings per share to be $3.50 to $3.80 compared to prior guidance of $2.90 to $3.30.