Tesla Inc. Chief Executive Elon Musk couldn’t resist some cannabis humor on Twitter on Monday.

That was the tweet Musk sent after Tesla’s stock TSLA, +5.04% hit the $420 level, referencing the 4/20 date, which is the unofficial cannabis holiday.

Other theories have had adherents, but it is believed the association among the number “420,” the date in April and cannabis was established by a group of San Francisco high schoolers in the ’70s, when meeting at 4:20 p.m. after school.

Musk, for his part, has had plenty to giggle over, after a period of controversy and relative stock stagnation. Tesla shares have gained 74% in the last three months, repeatedly notching records, buoyed by the surprise third-quarter profit unveiled in October.

Since then, excitement has built about the electric-car maker’s plans for China, where is it ramping up production at a new facility. The company is also fresh from the unveiling of its Cybertruck, with Musk boasting that the pickup already has received about 250,000 preorders, which require a $100 refundable deposit.

Tesla is expected to report fourth-quarter deliveries in early January, with fourth-quarter financial results likely in February.

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Analysts polled by FactSet expect the company to report an adjusted profit of $1.30 a share on sales of $6.7 billion. That would compare with an adjusted profit of $1.93 a share on sales of $7.2 billion in the year-ago period.