When Twitter (TWTR - Get Report) reports earnings Thursday, no one should be surprised that investors will be eyeing user numbers.

But everyone should be paying attention to the nuances.

For starters, Wall Street is looking for earnings per share of 20 cents, revenue of $874 million and total daily active users of 141 million, according to FactSet.

In focus will be a few more specific items.

Monetizable Daily Active Users

Twitter began including monetizable daily active users in its earnings reports, as the metric shows investors a better picture of how the company can generate revenue from its users.

RBC Capital Markets analyst Mark Mahaney is estimating MDAUs grew 14% year-over-year in the quarter and says any result better than 14% would be a considerable positive.

Daily active user growth more broadly has been hard to come by for the social media giant. Daily active users fell to 123 million in 2018 from 161.5 million in 2017. By the end of 2019, analysts expect Twitter's DAU count to hit 142.6 million.

Investors need to see Twitter's ability to sustain user growth.

Engagement and Advertising Trends

Goldman Sachs analyst Heath Terry wrote in a Tuesday note that users spent 38% more time on the platform year-over-year for both August and September.

That result matters a great deal, since higher user engagement usually means higher average revenue per user.

This trend seems to jibe with the ARPU trend, as analysts expect Twitter's total ARPU to increase 17%, 10% and 9% in 2019, 2020 and 2021, respectively. While user engagement can drive ARPU higher, advertisers must continue their spend on the platform. Fortunately for Twitter, Mahaney hinted that he expects advertisers to increase their spend on Twitter in the near future. He said 15% more advertisers RBC surveyed say they intend to increase their ad budgets on Twitter than those who say they'll pare them.

Longer Term

Twitter investors may need to see a large beat of expectations.

Twitter has had a rough recent past and is expected to see explosive financial results in 2019, followed by poor results in 2020, and then strong results again in 2021.

Earnings growth is expected to be a tripling for 2019, a drop of 49% in 2020, and then a rise of 25% in 2021. Meanwhile, the stock trades at 44 times next year's earnings.

Mahaney has his concerns.

"The company operates in the secular growth field of online advertising, which remains quite competitive, including from new entrants and well established competitors," he wrote in a Monday note.

"It is due to this competition and a relatively lower apparent value proposition to advertisers (but again, not users) that we see risk in the stock."

Wall Street has reiterated that Facebook (FB - Get Report) and Google (GOOGL - Get Report) represent the best return on ad spend for marketers. Twitter, on the other hand, has a platform less conducive to user intent to buy.

With that in mind, Twitter must hammer home to investors its ability to appeal to users in order to maximize its revenue opportunity.

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