与LTV相关的因素主要有：ARPU（平均单个用户收入）、用户流失率（其倒数为用户生命周期）、服务单个用户成本、CAC（获客成本）。这几个因素之间是相互影响的，它们的背后实质是公司行为和用户行为之间的互动结果。因此，在计算LTV时所使用的假设应该是基于业务实际情况进行的谨慎且合理的推断。投资人和管理层的出发点在有些时候可能不同，投资人需要减少风险，创业者需要加大投入推进业务。这就造成大家所使用的假设可能不同，假设的合理性与否就要看各自的职业判断能力了。 实际上，计算LTV并不需要得到特别精确的数字，只要平衡谨慎性和合理性原则对各个参数进行假设得到有价值的决策结果即可。 Lifetime value is the present value of the future net profit from the customer over the duration of the relationship. It helps determine the long-term value of the customer and how much net value you generate per customer after accounting for customer acquisition costs (CAC).
A common mistake is to estimate the LTV as a present value of revenue or even gross margin of the customer instead of calculating it as net profit of the customer over the life of the relationship. Reminder, here’s a way to calculate LTV:
Revenue per customer (per month) = average order value multiplied by the number of orders.
Contribution margin per customer (per month) = revenue from customer minus variable costs associated with a customer. Variable costs include selling, administrative and any operational costs associated with serving the customer. Avg. life span of customer (in months) = 1 / by your monthly churn.
LTV = Contribution margin from customer multiplied by the average lifespan of customer.
Note, if you have only few months of data, the conservative way to measure LTV is to look at historical value to date. Rather than predicting average life span and estimating how the retention curves might look, we prefer to measure 12 month and 24 month LTV.
Another important calculation here is LTV as it contributes to margin. This is important because a revenue or gross margin LTV suggests a higher upper limit on what you can spend on customer acquisition. Contribution Margin LTV to CAC ratio is also a good measure to determine CAC payback and manage your advertising and marketing spend accordingly.
第七、 总成交额vs.收入（Gross Merchandise Value (GMV) vs. Revenue）
这是非常传统的电商和交易平台指标，在撮合交易平台上适用。 GMV通常是针对交易平台而言的，它衡量的是特定期间里平台上发生的交易流水总额。它说明了交易平台对流量的吸纳能力。
交易平台的收入包括其在GMV里的提成（takes）、广告收入及其他增值服务收费。
In marketplace businesses, these are frequently used interchangeably. But GMV does not equal revenue!
GMV (gross merchandise volume) is the total sales dollar volume of merchandise transacting through the marketplace in a specific period. It’s the real top line, what the consumer side of the marketplace is spending. It is a
useful measure of the size of the marketplace and can be useful as a “current run rate” measure based on annualizing the most recent month or quarter. Revenue is the portion of GMV that the marketplace “takes”. Revenue consists of the various fees that the marketplace gets for providing its services; most typically these are transaction fees based on GMV successfully transacted on the marketplace, but can also include ad revenue, sponsorships, etc. These fees are usually a fraction of GMV.
第八、未实现收益（预收账款）以及开票额（Unearned or Deferred Revenue … and Billings）
这是一个会计确认的问题。根据会计准则，公司不得把尚未履行的服务所产生的经济流入确认为收入项目。
在形式上，预收账款项目记录的就是用户对已签约但尚未履行服务的合同提前向公司支付的款项。因此公司财务必须把这部分提前收到的款项作为对客户的负债记录在资产负债表上。
当公司履行了预收账款所对应的服务后，公司才可以在当月把这部分被作为负债的“未实现收益”从资产负债表转到利润表里确认为收入（即所谓“已实现收益”）。
Billing的意思是开收据，在公司在收到客户预付款项时需要开具收据并记录，当相应的款项符合收入确认条件时向客户开具发票。Billing是财务流程中的一个动作，其本身不属于财务报告概念。
当期Billing这个数字所代表的是公司从用户那里收到的全部现金金额。它反映了公司对用户的议价能力、押款能力，如果Billing的增长势头好，可能说明公司的业务进入强势增长阶段。
In a SaaS business, this is the cash you collect at the time of the booking in advance of when the revenues will actually be realized.
As we’ve shared previously, SaaS companies only get to recognize revenue over the term of the deal as the service is delivered — even if a customer signs a huge up-front deal. So in most cases, that “booking” goes onto the balance sheet in a liability line item called deferred revenue. (Because the balance sheet has to “balance,” the corresponding entry on the assets side of the balance sheet is “cash” if the customer pre-paid for the service or “accounts receivable” if the company expects to bill for and receive it in the future). As the company starts to recognize revenue from the software as service, it reduces its deferred revenue balance and increases revenue: for a 24-month deal, as each month goes by deferred revenue drops by 1/24th and revenue increases by 1/24th.
A good proxy to measure the growth — and ultimately the health — of a SaaS company is to look at billings, which is calculated by taking the revenue in one quarter and adding the change in deferred revenue from the prior quarter to the current quarter. If a SaaS company is growing its bookings (whether through new business or upsells/renewals to existing customers), billings will increase.
Billings is a much better forward-looking indicator of the health of a SaaS company than simply looking at revenue because revenue understates the true value of the customer, which gets recognized ratably. But it’s also tricky because of the very nature of recurring revenue itself: A SaaS company could
show stable revenue for a long time — just by working off its billings backlog — which would make the business seem healthier than it truly is. This is something we therefore watch out for when evaluating the unit economics of such businesses.
第二部分：产品与用户指标（Product and Engagement Metrics） 产品和用户指标的定义千差万别，对于指标的选取和定义标准对于做出正确的投资分析和运营决策至关重要。 第九、活跃用户数（Active Users）
活跃用户是需要被加以定义的，原则上说，投资人一定会给一个谨慎的评判标准来衡量什么样的用户才是“活跃”的。这需要根据行业特征通过具体场景加以界定。
Different companies have almost unlimited definitions for what “active” means. Some charts don’t even define what that activity is, while others include inadvertent activity — such as having a high proportion of first-time users or accidental one-time users.
Be clear on how you define “active.”
第十、环比增长率（Month-on-month (MoM) growth）
普通环比增长率受到短期因素的影响波动可能较大，其对比价值有限。 因此，投资人会选择使用复合环比增长率（CMGC）作为环比数据的分析指标。
CMGC=(当前月数字/基础月数字)^(1/月份数目) - 1