I'm not so sure God cares how big your church is. Seriously. If your numbers aren't "growing," so what? I'm also not sure that the sign of a vibrant healthy church is ever-increasing growth, significant growth. It seems to me that the sign of a vibrant, healthy fully alive church is one where God's people are growing in love, knowledge, and insight, not numbers. I'd rather be in a church like this than a church that is "growing" with greater numbers of people with shallow faiths who do not love well.
Where did Paul ever rebuke a church because their numbers were not growing by some set of hoped for percentage points?
Philippians 1:9-11. And this is my prayer: that your love may abound more and more in knowledge and depth of insight, 10 so that you may be able to discern what is best and may be pure and blameless for the day of Christ, 11 filled with the fruit of righteousness that comes through Jesus Christ—to the glory and praise of God.
Westminster Confession of Faith, Chapter 25 on "The Church:"
III. Unto this catholic visible Church Christ has given the ministry, oracles, and ordinances of God, for the gathering and perfecting of the saints, in this life, to end of the world: and does, by His own presence and Spirit, according to His promise, make them effectual thereunto.